SemaInit.cpp revision 81359b0a88510087a873de771f9a2f5ee7ed97d9
1//===--- SemaInit.cpp - Semantic Analysis for Initializers ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for initializers. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/Initialization.h" 15#include "clang/AST/ASTContext.h" 16#include "clang/AST/DeclObjC.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/ExprObjC.h" 19#include "clang/AST/TypeLoc.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/Sema/Designator.h" 22#include "clang/Sema/Lookup.h" 23#include "clang/Sema/SemaInternal.h" 24#include "llvm/ADT/APInt.h" 25#include "llvm/ADT/SmallString.h" 26#include "llvm/Support/ErrorHandling.h" 27#include "llvm/Support/raw_ostream.h" 28#include <map> 29using namespace clang; 30 31//===----------------------------------------------------------------------===// 32// Sema Initialization Checking 33//===----------------------------------------------------------------------===// 34 35/// \brief Check whether T is compatible with a wide character type (wchar_t, 36/// char16_t or char32_t). 37static bool IsWideCharCompatible(QualType T, ASTContext &Context) { 38 if (Context.typesAreCompatible(Context.getWideCharType(), T)) 39 return true; 40 if (Context.getLangOpts().CPlusPlus || Context.getLangOpts().C11) { 41 return Context.typesAreCompatible(Context.Char16Ty, T) || 42 Context.typesAreCompatible(Context.Char32Ty, T); 43 } 44 return false; 45} 46 47enum StringInitFailureKind { 48 SIF_None, 49 SIF_NarrowStringIntoWideChar, 50 SIF_WideStringIntoChar, 51 SIF_IncompatWideStringIntoWideChar, 52 SIF_Other 53}; 54 55/// \brief Check whether the array of type AT can be initialized by the Init 56/// expression by means of string initialization. Returns SIF_None if so, 57/// otherwise returns a StringInitFailureKind that describes why the 58/// initialization would not work. 59static StringInitFailureKind IsStringInit(Expr *Init, const ArrayType *AT, 60 ASTContext &Context) { 61 if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT)) 62 return SIF_Other; 63 64 // See if this is a string literal or @encode. 65 Init = Init->IgnoreParens(); 66 67 // Handle @encode, which is a narrow string. 68 if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType()) 69 return SIF_None; 70 71 // Otherwise we can only handle string literals. 72 StringLiteral *SL = dyn_cast<StringLiteral>(Init); 73 if (SL == 0) 74 return SIF_Other; 75 76 const QualType ElemTy = 77 Context.getCanonicalType(AT->getElementType()).getUnqualifiedType(); 78 79 switch (SL->getKind()) { 80 case StringLiteral::Ascii: 81 case StringLiteral::UTF8: 82 // char array can be initialized with a narrow string. 83 // Only allow char x[] = "foo"; not char x[] = L"foo"; 84 if (ElemTy->isCharType()) 85 return SIF_None; 86 if (IsWideCharCompatible(ElemTy, Context)) 87 return SIF_NarrowStringIntoWideChar; 88 return SIF_Other; 89 // C99 6.7.8p15 (with correction from DR343), or C11 6.7.9p15: 90 // "An array with element type compatible with a qualified or unqualified 91 // version of wchar_t, char16_t, or char32_t may be initialized by a wide 92 // string literal with the corresponding encoding prefix (L, u, or U, 93 // respectively), optionally enclosed in braces. 94 case StringLiteral::UTF16: 95 if (Context.typesAreCompatible(Context.Char16Ty, ElemTy)) 96 return SIF_None; 97 if (ElemTy->isCharType()) 98 return SIF_WideStringIntoChar; 99 if (IsWideCharCompatible(ElemTy, Context)) 100 return SIF_IncompatWideStringIntoWideChar; 101 return SIF_Other; 102 case StringLiteral::UTF32: 103 if (Context.typesAreCompatible(Context.Char32Ty, ElemTy)) 104 return SIF_None; 105 if (ElemTy->isCharType()) 106 return SIF_WideStringIntoChar; 107 if (IsWideCharCompatible(ElemTy, Context)) 108 return SIF_IncompatWideStringIntoWideChar; 109 return SIF_Other; 110 case StringLiteral::Wide: 111 if (Context.typesAreCompatible(Context.getWideCharType(), ElemTy)) 112 return SIF_None; 113 if (ElemTy->isCharType()) 114 return SIF_WideStringIntoChar; 115 if (IsWideCharCompatible(ElemTy, Context)) 116 return SIF_IncompatWideStringIntoWideChar; 117 return SIF_Other; 118 } 119 120 llvm_unreachable("missed a StringLiteral kind?"); 121} 122 123static StringInitFailureKind IsStringInit(Expr *init, QualType declType, 124 ASTContext &Context) { 125 const ArrayType *arrayType = Context.getAsArrayType(declType); 126 if (!arrayType) 127 return SIF_Other; 128 return IsStringInit(init, arrayType, Context); 129} 130 131/// Update the type of a string literal, including any surrounding parentheses, 132/// to match the type of the object which it is initializing. 133static void updateStringLiteralType(Expr *E, QualType Ty) { 134 while (true) { 135 E->setType(Ty); 136 if (isa<StringLiteral>(E) || isa<ObjCEncodeExpr>(E)) 137 break; 138 else if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) 139 E = PE->getSubExpr(); 140 else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) 141 E = UO->getSubExpr(); 142 else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E)) 143 E = GSE->getResultExpr(); 144 else 145 llvm_unreachable("unexpected expr in string literal init"); 146 } 147} 148 149static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT, 150 Sema &S) { 151 // Get the length of the string as parsed. 152 uint64_t StrLength = 153 cast<ConstantArrayType>(Str->getType())->getSize().getZExtValue(); 154 155 156 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 157 // C99 6.7.8p14. We have an array of character type with unknown size 158 // being initialized to a string literal. 159 llvm::APInt ConstVal(32, StrLength); 160 // Return a new array type (C99 6.7.8p22). 161 DeclT = S.Context.getConstantArrayType(IAT->getElementType(), 162 ConstVal, 163 ArrayType::Normal, 0); 164 updateStringLiteralType(Str, DeclT); 165 return; 166 } 167 168 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 169 170 // We have an array of character type with known size. However, 171 // the size may be smaller or larger than the string we are initializing. 172 // FIXME: Avoid truncation for 64-bit length strings. 173 if (S.getLangOpts().CPlusPlus) { 174 if (StringLiteral *SL = dyn_cast<StringLiteral>(Str->IgnoreParens())) { 175 // For Pascal strings it's OK to strip off the terminating null character, 176 // so the example below is valid: 177 // 178 // unsigned char a[2] = "\pa"; 179 if (SL->isPascal()) 180 StrLength--; 181 } 182 183 // [dcl.init.string]p2 184 if (StrLength > CAT->getSize().getZExtValue()) 185 S.Diag(Str->getLocStart(), 186 diag::err_initializer_string_for_char_array_too_long) 187 << Str->getSourceRange(); 188 } else { 189 // C99 6.7.8p14. 190 if (StrLength-1 > CAT->getSize().getZExtValue()) 191 S.Diag(Str->getLocStart(), 192 diag::warn_initializer_string_for_char_array_too_long) 193 << Str->getSourceRange(); 194 } 195 196 // Set the type to the actual size that we are initializing. If we have 197 // something like: 198 // char x[1] = "foo"; 199 // then this will set the string literal's type to char[1]. 200 updateStringLiteralType(Str, DeclT); 201} 202 203//===----------------------------------------------------------------------===// 204// Semantic checking for initializer lists. 205//===----------------------------------------------------------------------===// 206 207/// @brief Semantic checking for initializer lists. 208/// 209/// The InitListChecker class contains a set of routines that each 210/// handle the initialization of a certain kind of entity, e.g., 211/// arrays, vectors, struct/union types, scalars, etc. The 212/// InitListChecker itself performs a recursive walk of the subobject 213/// structure of the type to be initialized, while stepping through 214/// the initializer list one element at a time. The IList and Index 215/// parameters to each of the Check* routines contain the active 216/// (syntactic) initializer list and the index into that initializer 217/// list that represents the current initializer. Each routine is 218/// responsible for moving that Index forward as it consumes elements. 219/// 220/// Each Check* routine also has a StructuredList/StructuredIndex 221/// arguments, which contains the current "structured" (semantic) 222/// initializer list and the index into that initializer list where we 223/// are copying initializers as we map them over to the semantic 224/// list. Once we have completed our recursive walk of the subobject 225/// structure, we will have constructed a full semantic initializer 226/// list. 227/// 228/// C99 designators cause changes in the initializer list traversal, 229/// because they make the initialization "jump" into a specific 230/// subobject and then continue the initialization from that 231/// point. CheckDesignatedInitializer() recursively steps into the 232/// designated subobject and manages backing out the recursion to 233/// initialize the subobjects after the one designated. 234namespace { 235class InitListChecker { 236 Sema &SemaRef; 237 bool hadError; 238 bool VerifyOnly; // no diagnostics, no structure building 239 llvm::DenseMap<InitListExpr *, InitListExpr *> SyntacticToSemantic; 240 InitListExpr *FullyStructuredList; 241 242 void CheckImplicitInitList(const InitializedEntity &Entity, 243 InitListExpr *ParentIList, QualType T, 244 unsigned &Index, InitListExpr *StructuredList, 245 unsigned &StructuredIndex); 246 void CheckExplicitInitList(const InitializedEntity &Entity, 247 InitListExpr *IList, QualType &T, 248 unsigned &Index, InitListExpr *StructuredList, 249 unsigned &StructuredIndex, 250 bool TopLevelObject = false); 251 void CheckListElementTypes(const InitializedEntity &Entity, 252 InitListExpr *IList, QualType &DeclType, 253 bool SubobjectIsDesignatorContext, 254 unsigned &Index, 255 InitListExpr *StructuredList, 256 unsigned &StructuredIndex, 257 bool TopLevelObject = false); 258 void CheckSubElementType(const InitializedEntity &Entity, 259 InitListExpr *IList, QualType ElemType, 260 unsigned &Index, 261 InitListExpr *StructuredList, 262 unsigned &StructuredIndex); 263 void CheckComplexType(const InitializedEntity &Entity, 264 InitListExpr *IList, QualType DeclType, 265 unsigned &Index, 266 InitListExpr *StructuredList, 267 unsigned &StructuredIndex); 268 void CheckScalarType(const InitializedEntity &Entity, 269 InitListExpr *IList, QualType DeclType, 270 unsigned &Index, 271 InitListExpr *StructuredList, 272 unsigned &StructuredIndex); 273 void CheckReferenceType(const InitializedEntity &Entity, 274 InitListExpr *IList, QualType DeclType, 275 unsigned &Index, 276 InitListExpr *StructuredList, 277 unsigned &StructuredIndex); 278 void CheckVectorType(const InitializedEntity &Entity, 279 InitListExpr *IList, QualType DeclType, unsigned &Index, 280 InitListExpr *StructuredList, 281 unsigned &StructuredIndex); 282 void CheckStructUnionTypes(const InitializedEntity &Entity, 283 InitListExpr *IList, QualType DeclType, 284 RecordDecl::field_iterator Field, 285 bool SubobjectIsDesignatorContext, unsigned &Index, 286 InitListExpr *StructuredList, 287 unsigned &StructuredIndex, 288 bool TopLevelObject = false); 289 void CheckArrayType(const InitializedEntity &Entity, 290 InitListExpr *IList, QualType &DeclType, 291 llvm::APSInt elementIndex, 292 bool SubobjectIsDesignatorContext, unsigned &Index, 293 InitListExpr *StructuredList, 294 unsigned &StructuredIndex); 295 bool CheckDesignatedInitializer(const InitializedEntity &Entity, 296 InitListExpr *IList, DesignatedInitExpr *DIE, 297 unsigned DesigIdx, 298 QualType &CurrentObjectType, 299 RecordDecl::field_iterator *NextField, 300 llvm::APSInt *NextElementIndex, 301 unsigned &Index, 302 InitListExpr *StructuredList, 303 unsigned &StructuredIndex, 304 bool FinishSubobjectInit, 305 bool TopLevelObject); 306 InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, 307 QualType CurrentObjectType, 308 InitListExpr *StructuredList, 309 unsigned StructuredIndex, 310 SourceRange InitRange); 311 void UpdateStructuredListElement(InitListExpr *StructuredList, 312 unsigned &StructuredIndex, 313 Expr *expr); 314 int numArrayElements(QualType DeclType); 315 int numStructUnionElements(QualType DeclType); 316 317 void FillInValueInitForField(unsigned Init, FieldDecl *Field, 318 const InitializedEntity &ParentEntity, 319 InitListExpr *ILE, bool &RequiresSecondPass); 320 void FillInValueInitializations(const InitializedEntity &Entity, 321 InitListExpr *ILE, bool &RequiresSecondPass); 322 bool CheckFlexibleArrayInit(const InitializedEntity &Entity, 323 Expr *InitExpr, FieldDecl *Field, 324 bool TopLevelObject); 325 void CheckValueInitializable(const InitializedEntity &Entity); 326 327public: 328 InitListChecker(Sema &S, const InitializedEntity &Entity, 329 InitListExpr *IL, QualType &T, bool VerifyOnly); 330 bool HadError() { return hadError; } 331 332 // @brief Retrieves the fully-structured initializer list used for 333 // semantic analysis and code generation. 334 InitListExpr *getFullyStructuredList() const { return FullyStructuredList; } 335}; 336} // end anonymous namespace 337 338void InitListChecker::CheckValueInitializable(const InitializedEntity &Entity) { 339 assert(VerifyOnly && 340 "CheckValueInitializable is only inteded for verification mode."); 341 342 SourceLocation Loc; 343 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 344 true); 345 InitializationSequence InitSeq(SemaRef, Entity, Kind, None); 346 if (InitSeq.Failed()) 347 hadError = true; 348} 349 350void InitListChecker::FillInValueInitForField(unsigned Init, FieldDecl *Field, 351 const InitializedEntity &ParentEntity, 352 InitListExpr *ILE, 353 bool &RequiresSecondPass) { 354 SourceLocation Loc = ILE->getLocStart(); 355 unsigned NumInits = ILE->getNumInits(); 356 InitializedEntity MemberEntity 357 = InitializedEntity::InitializeMember(Field, &ParentEntity); 358 if (Init >= NumInits || !ILE->getInit(Init)) { 359 // If there's no explicit initializer but we have a default initializer, use 360 // that. This only happens in C++1y, since classes with default 361 // initializers are not aggregates in C++11. 362 if (Field->hasInClassInitializer()) { 363 Expr *DIE = CXXDefaultInitExpr::Create(SemaRef.Context, 364 ILE->getRBraceLoc(), Field); 365 if (Init < NumInits) 366 ILE->setInit(Init, DIE); 367 else { 368 ILE->updateInit(SemaRef.Context, Init, DIE); 369 RequiresSecondPass = true; 370 } 371 return; 372 } 373 374 // FIXME: We probably don't need to handle references 375 // specially here, since value-initialization of references is 376 // handled in InitializationSequence. 377 if (Field->getType()->isReferenceType()) { 378 // C++ [dcl.init.aggr]p9: 379 // If an incomplete or empty initializer-list leaves a 380 // member of reference type uninitialized, the program is 381 // ill-formed. 382 SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized) 383 << Field->getType() 384 << ILE->getSyntacticForm()->getSourceRange(); 385 SemaRef.Diag(Field->getLocation(), 386 diag::note_uninit_reference_member); 387 hadError = true; 388 return; 389 } 390 391 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 392 true); 393 InitializationSequence InitSeq(SemaRef, MemberEntity, Kind, None); 394 if (!InitSeq) { 395 InitSeq.Diagnose(SemaRef, MemberEntity, Kind, None); 396 hadError = true; 397 return; 398 } 399 400 ExprResult MemberInit 401 = InitSeq.Perform(SemaRef, MemberEntity, Kind, None); 402 if (MemberInit.isInvalid()) { 403 hadError = true; 404 return; 405 } 406 407 if (hadError) { 408 // Do nothing 409 } else if (Init < NumInits) { 410 ILE->setInit(Init, MemberInit.takeAs<Expr>()); 411 } else if (InitSeq.isConstructorInitialization()) { 412 // Value-initialization requires a constructor call, so 413 // extend the initializer list to include the constructor 414 // call and make a note that we'll need to take another pass 415 // through the initializer list. 416 ILE->updateInit(SemaRef.Context, Init, MemberInit.takeAs<Expr>()); 417 RequiresSecondPass = true; 418 } 419 } else if (InitListExpr *InnerILE 420 = dyn_cast<InitListExpr>(ILE->getInit(Init))) 421 FillInValueInitializations(MemberEntity, InnerILE, 422 RequiresSecondPass); 423} 424 425/// Recursively replaces NULL values within the given initializer list 426/// with expressions that perform value-initialization of the 427/// appropriate type. 428void 429InitListChecker::FillInValueInitializations(const InitializedEntity &Entity, 430 InitListExpr *ILE, 431 bool &RequiresSecondPass) { 432 assert((ILE->getType() != SemaRef.Context.VoidTy) && 433 "Should not have void type"); 434 SourceLocation Loc = ILE->getLocStart(); 435 if (ILE->getSyntacticForm()) 436 Loc = ILE->getSyntacticForm()->getLocStart(); 437 438 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) { 439 const RecordDecl *RDecl = RType->getDecl(); 440 if (RDecl->isUnion() && ILE->getInitializedFieldInUnion()) 441 FillInValueInitForField(0, ILE->getInitializedFieldInUnion(), 442 Entity, ILE, RequiresSecondPass); 443 else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) && 444 cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) { 445 for (RecordDecl::field_iterator Field = RDecl->field_begin(), 446 FieldEnd = RDecl->field_end(); 447 Field != FieldEnd; ++Field) { 448 if (Field->hasInClassInitializer()) { 449 FillInValueInitForField(0, *Field, Entity, ILE, RequiresSecondPass); 450 break; 451 } 452 } 453 } else { 454 unsigned Init = 0; 455 for (RecordDecl::field_iterator Field = RDecl->field_begin(), 456 FieldEnd = RDecl->field_end(); 457 Field != FieldEnd; ++Field) { 458 if (Field->isUnnamedBitfield()) 459 continue; 460 461 if (hadError) 462 return; 463 464 FillInValueInitForField(Init, *Field, Entity, ILE, RequiresSecondPass); 465 if (hadError) 466 return; 467 468 ++Init; 469 470 // Only look at the first initialization of a union. 471 if (RDecl->isUnion()) 472 break; 473 } 474 } 475 476 return; 477 } 478 479 QualType ElementType; 480 481 InitializedEntity ElementEntity = Entity; 482 unsigned NumInits = ILE->getNumInits(); 483 unsigned NumElements = NumInits; 484 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) { 485 ElementType = AType->getElementType(); 486 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) 487 NumElements = CAType->getSize().getZExtValue(); 488 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, 489 0, Entity); 490 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) { 491 ElementType = VType->getElementType(); 492 NumElements = VType->getNumElements(); 493 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context, 494 0, Entity); 495 } else 496 ElementType = ILE->getType(); 497 498 499 for (unsigned Init = 0; Init != NumElements; ++Init) { 500 if (hadError) 501 return; 502 503 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement || 504 ElementEntity.getKind() == InitializedEntity::EK_VectorElement) 505 ElementEntity.setElementIndex(Init); 506 507 Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : 0); 508 if (!InitExpr && !ILE->hasArrayFiller()) { 509 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc, 510 true); 511 InitializationSequence InitSeq(SemaRef, ElementEntity, Kind, None); 512 if (!InitSeq) { 513 InitSeq.Diagnose(SemaRef, ElementEntity, Kind, None); 514 hadError = true; 515 return; 516 } 517 518 ExprResult ElementInit 519 = InitSeq.Perform(SemaRef, ElementEntity, Kind, None); 520 if (ElementInit.isInvalid()) { 521 hadError = true; 522 return; 523 } 524 525 if (hadError) { 526 // Do nothing 527 } else if (Init < NumInits) { 528 // For arrays, just set the expression used for value-initialization 529 // of the "holes" in the array. 530 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) 531 ILE->setArrayFiller(ElementInit.takeAs<Expr>()); 532 else 533 ILE->setInit(Init, ElementInit.takeAs<Expr>()); 534 } else { 535 // For arrays, just set the expression used for value-initialization 536 // of the rest of elements and exit. 537 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) { 538 ILE->setArrayFiller(ElementInit.takeAs<Expr>()); 539 return; 540 } 541 542 if (InitSeq.isConstructorInitialization()) { 543 // Value-initialization requires a constructor call, so 544 // extend the initializer list to include the constructor 545 // call and make a note that we'll need to take another pass 546 // through the initializer list. 547 ILE->updateInit(SemaRef.Context, Init, ElementInit.takeAs<Expr>()); 548 RequiresSecondPass = true; 549 } 550 } 551 } else if (InitListExpr *InnerILE 552 = dyn_cast_or_null<InitListExpr>(InitExpr)) 553 FillInValueInitializations(ElementEntity, InnerILE, RequiresSecondPass); 554 } 555} 556 557 558InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity, 559 InitListExpr *IL, QualType &T, 560 bool VerifyOnly) 561 : SemaRef(S), VerifyOnly(VerifyOnly) { 562 hadError = false; 563 564 unsigned newIndex = 0; 565 unsigned newStructuredIndex = 0; 566 FullyStructuredList 567 = getStructuredSubobjectInit(IL, newIndex, T, 0, 0, IL->getSourceRange()); 568 CheckExplicitInitList(Entity, IL, T, newIndex, 569 FullyStructuredList, newStructuredIndex, 570 /*TopLevelObject=*/true); 571 572 if (!hadError && !VerifyOnly) { 573 bool RequiresSecondPass = false; 574 FillInValueInitializations(Entity, FullyStructuredList, RequiresSecondPass); 575 if (RequiresSecondPass && !hadError) 576 FillInValueInitializations(Entity, FullyStructuredList, 577 RequiresSecondPass); 578 } 579} 580 581int InitListChecker::numArrayElements(QualType DeclType) { 582 // FIXME: use a proper constant 583 int maxElements = 0x7FFFFFFF; 584 if (const ConstantArrayType *CAT = 585 SemaRef.Context.getAsConstantArrayType(DeclType)) { 586 maxElements = static_cast<int>(CAT->getSize().getZExtValue()); 587 } 588 return maxElements; 589} 590 591int InitListChecker::numStructUnionElements(QualType DeclType) { 592 RecordDecl *structDecl = DeclType->getAs<RecordType>()->getDecl(); 593 int InitializableMembers = 0; 594 for (RecordDecl::field_iterator 595 Field = structDecl->field_begin(), 596 FieldEnd = structDecl->field_end(); 597 Field != FieldEnd; ++Field) { 598 if (!Field->isUnnamedBitfield()) 599 ++InitializableMembers; 600 } 601 if (structDecl->isUnion()) 602 return std::min(InitializableMembers, 1); 603 return InitializableMembers - structDecl->hasFlexibleArrayMember(); 604} 605 606void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity, 607 InitListExpr *ParentIList, 608 QualType T, unsigned &Index, 609 InitListExpr *StructuredList, 610 unsigned &StructuredIndex) { 611 int maxElements = 0; 612 613 if (T->isArrayType()) 614 maxElements = numArrayElements(T); 615 else if (T->isRecordType()) 616 maxElements = numStructUnionElements(T); 617 else if (T->isVectorType()) 618 maxElements = T->getAs<VectorType>()->getNumElements(); 619 else 620 llvm_unreachable("CheckImplicitInitList(): Illegal type"); 621 622 if (maxElements == 0) { 623 if (!VerifyOnly) 624 SemaRef.Diag(ParentIList->getInit(Index)->getLocStart(), 625 diag::err_implicit_empty_initializer); 626 ++Index; 627 hadError = true; 628 return; 629 } 630 631 // Build a structured initializer list corresponding to this subobject. 632 InitListExpr *StructuredSubobjectInitList 633 = getStructuredSubobjectInit(ParentIList, Index, T, StructuredList, 634 StructuredIndex, 635 SourceRange(ParentIList->getInit(Index)->getLocStart(), 636 ParentIList->getSourceRange().getEnd())); 637 unsigned StructuredSubobjectInitIndex = 0; 638 639 // Check the element types and build the structural subobject. 640 unsigned StartIndex = Index; 641 CheckListElementTypes(Entity, ParentIList, T, 642 /*SubobjectIsDesignatorContext=*/false, Index, 643 StructuredSubobjectInitList, 644 StructuredSubobjectInitIndex); 645 646 if (!VerifyOnly) { 647 StructuredSubobjectInitList->setType(T); 648 649 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1); 650 // Update the structured sub-object initializer so that it's ending 651 // range corresponds with the end of the last initializer it used. 652 if (EndIndex < ParentIList->getNumInits()) { 653 SourceLocation EndLoc 654 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd(); 655 StructuredSubobjectInitList->setRBraceLoc(EndLoc); 656 } 657 658 // Complain about missing braces. 659 if (T->isArrayType() || T->isRecordType()) { 660 SemaRef.Diag(StructuredSubobjectInitList->getLocStart(), 661 diag::warn_missing_braces) 662 << StructuredSubobjectInitList->getSourceRange() 663 << FixItHint::CreateInsertion( 664 StructuredSubobjectInitList->getLocStart(), "{") 665 << FixItHint::CreateInsertion( 666 SemaRef.PP.getLocForEndOfToken( 667 StructuredSubobjectInitList->getLocEnd()), 668 "}"); 669 } 670 } 671} 672 673void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity, 674 InitListExpr *IList, QualType &T, 675 unsigned &Index, 676 InitListExpr *StructuredList, 677 unsigned &StructuredIndex, 678 bool TopLevelObject) { 679 assert(IList->isExplicit() && "Illegal Implicit InitListExpr"); 680 if (!VerifyOnly) { 681 SyntacticToSemantic[IList] = StructuredList; 682 StructuredList->setSyntacticForm(IList); 683 } 684 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true, 685 Index, StructuredList, StructuredIndex, TopLevelObject); 686 if (!VerifyOnly) { 687 QualType ExprTy = T; 688 if (!ExprTy->isArrayType()) 689 ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context); 690 IList->setType(ExprTy); 691 StructuredList->setType(ExprTy); 692 } 693 if (hadError) 694 return; 695 696 if (Index < IList->getNumInits()) { 697 // We have leftover initializers 698 if (VerifyOnly) { 699 if (SemaRef.getLangOpts().CPlusPlus || 700 (SemaRef.getLangOpts().OpenCL && 701 IList->getType()->isVectorType())) { 702 hadError = true; 703 } 704 return; 705 } 706 707 if (StructuredIndex == 1 && 708 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context) == 709 SIF_None) { 710 unsigned DK = diag::warn_excess_initializers_in_char_array_initializer; 711 if (SemaRef.getLangOpts().CPlusPlus) { 712 DK = diag::err_excess_initializers_in_char_array_initializer; 713 hadError = true; 714 } 715 // Special-case 716 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) 717 << IList->getInit(Index)->getSourceRange(); 718 } else if (!T->isIncompleteType()) { 719 // Don't complain for incomplete types, since we'll get an error 720 // elsewhere 721 QualType CurrentObjectType = StructuredList->getType(); 722 int initKind = 723 CurrentObjectType->isArrayType()? 0 : 724 CurrentObjectType->isVectorType()? 1 : 725 CurrentObjectType->isScalarType()? 2 : 726 CurrentObjectType->isUnionType()? 3 : 727 4; 728 729 unsigned DK = diag::warn_excess_initializers; 730 if (SemaRef.getLangOpts().CPlusPlus) { 731 DK = diag::err_excess_initializers; 732 hadError = true; 733 } 734 if (SemaRef.getLangOpts().OpenCL && initKind == 1) { 735 DK = diag::err_excess_initializers; 736 hadError = true; 737 } 738 739 SemaRef.Diag(IList->getInit(Index)->getLocStart(), DK) 740 << initKind << IList->getInit(Index)->getSourceRange(); 741 } 742 } 743 744 if (!VerifyOnly && T->isScalarType() && IList->getNumInits() == 1 && 745 !TopLevelObject) 746 SemaRef.Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init) 747 << IList->getSourceRange() 748 << FixItHint::CreateRemoval(IList->getLocStart()) 749 << FixItHint::CreateRemoval(IList->getLocEnd()); 750} 751 752void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity, 753 InitListExpr *IList, 754 QualType &DeclType, 755 bool SubobjectIsDesignatorContext, 756 unsigned &Index, 757 InitListExpr *StructuredList, 758 unsigned &StructuredIndex, 759 bool TopLevelObject) { 760 if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) { 761 // Explicitly braced initializer for complex type can be real+imaginary 762 // parts. 763 CheckComplexType(Entity, IList, DeclType, Index, 764 StructuredList, StructuredIndex); 765 } else if (DeclType->isScalarType()) { 766 CheckScalarType(Entity, IList, DeclType, Index, 767 StructuredList, StructuredIndex); 768 } else if (DeclType->isVectorType()) { 769 CheckVectorType(Entity, IList, DeclType, Index, 770 StructuredList, StructuredIndex); 771 } else if (DeclType->isRecordType()) { 772 assert(DeclType->isAggregateType() && 773 "non-aggregate records should be handed in CheckSubElementType"); 774 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 775 CheckStructUnionTypes(Entity, IList, DeclType, RD->field_begin(), 776 SubobjectIsDesignatorContext, Index, 777 StructuredList, StructuredIndex, 778 TopLevelObject); 779 } else if (DeclType->isArrayType()) { 780 llvm::APSInt Zero( 781 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()), 782 false); 783 CheckArrayType(Entity, IList, DeclType, Zero, 784 SubobjectIsDesignatorContext, Index, 785 StructuredList, StructuredIndex); 786 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) { 787 // This type is invalid, issue a diagnostic. 788 ++Index; 789 if (!VerifyOnly) 790 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) 791 << DeclType; 792 hadError = true; 793 } else if (DeclType->isReferenceType()) { 794 CheckReferenceType(Entity, IList, DeclType, Index, 795 StructuredList, StructuredIndex); 796 } else if (DeclType->isObjCObjectType()) { 797 if (!VerifyOnly) 798 SemaRef.Diag(IList->getLocStart(), diag::err_init_objc_class) 799 << DeclType; 800 hadError = true; 801 } else { 802 if (!VerifyOnly) 803 SemaRef.Diag(IList->getLocStart(), diag::err_illegal_initializer_type) 804 << DeclType; 805 hadError = true; 806 } 807} 808 809void InitListChecker::CheckSubElementType(const InitializedEntity &Entity, 810 InitListExpr *IList, 811 QualType ElemType, 812 unsigned &Index, 813 InitListExpr *StructuredList, 814 unsigned &StructuredIndex) { 815 Expr *expr = IList->getInit(Index); 816 817 if (ElemType->isReferenceType()) 818 return CheckReferenceType(Entity, IList, ElemType, Index, 819 StructuredList, StructuredIndex); 820 821 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 822 if (!ElemType->isRecordType() || ElemType->isAggregateType()) { 823 unsigned newIndex = 0; 824 unsigned newStructuredIndex = 0; 825 InitListExpr *newStructuredList 826 = getStructuredSubobjectInit(IList, Index, ElemType, 827 StructuredList, StructuredIndex, 828 SubInitList->getSourceRange()); 829 CheckExplicitInitList(Entity, SubInitList, ElemType, newIndex, 830 newStructuredList, newStructuredIndex); 831 ++StructuredIndex; 832 ++Index; 833 return; 834 } 835 assert(SemaRef.getLangOpts().CPlusPlus && 836 "non-aggregate records are only possible in C++"); 837 // C++ initialization is handled later. 838 } 839 840 if (ElemType->isScalarType()) 841 return CheckScalarType(Entity, IList, ElemType, Index, 842 StructuredList, StructuredIndex); 843 844 if (const ArrayType *arrayType = SemaRef.Context.getAsArrayType(ElemType)) { 845 // arrayType can be incomplete if we're initializing a flexible 846 // array member. There's nothing we can do with the completed 847 // type here, though. 848 849 if (IsStringInit(expr, arrayType, SemaRef.Context) == SIF_None) { 850 if (!VerifyOnly) { 851 CheckStringInit(expr, ElemType, arrayType, SemaRef); 852 UpdateStructuredListElement(StructuredList, StructuredIndex, expr); 853 } 854 ++Index; 855 return; 856 } 857 858 // Fall through for subaggregate initialization. 859 860 } else if (SemaRef.getLangOpts().CPlusPlus) { 861 // C++ [dcl.init.aggr]p12: 862 // All implicit type conversions (clause 4) are considered when 863 // initializing the aggregate member with an initializer from 864 // an initializer-list. If the initializer can initialize a 865 // member, the member is initialized. [...] 866 867 // FIXME: Better EqualLoc? 868 InitializationKind Kind = 869 InitializationKind::CreateCopy(expr->getLocStart(), SourceLocation()); 870 InitializationSequence Seq(SemaRef, Entity, Kind, expr); 871 872 if (Seq) { 873 if (!VerifyOnly) { 874 ExprResult Result = 875 Seq.Perform(SemaRef, Entity, Kind, expr); 876 if (Result.isInvalid()) 877 hadError = true; 878 879 UpdateStructuredListElement(StructuredList, StructuredIndex, 880 Result.takeAs<Expr>()); 881 } 882 ++Index; 883 return; 884 } 885 886 // Fall through for subaggregate initialization 887 } else { 888 // C99 6.7.8p13: 889 // 890 // The initializer for a structure or union object that has 891 // automatic storage duration shall be either an initializer 892 // list as described below, or a single expression that has 893 // compatible structure or union type. In the latter case, the 894 // initial value of the object, including unnamed members, is 895 // that of the expression. 896 ExprResult ExprRes = SemaRef.Owned(expr); 897 if ((ElemType->isRecordType() || ElemType->isVectorType()) && 898 SemaRef.CheckSingleAssignmentConstraints(ElemType, ExprRes, 899 !VerifyOnly) 900 == Sema::Compatible) { 901 if (ExprRes.isInvalid()) 902 hadError = true; 903 else { 904 ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.take()); 905 if (ExprRes.isInvalid()) 906 hadError = true; 907 } 908 UpdateStructuredListElement(StructuredList, StructuredIndex, 909 ExprRes.takeAs<Expr>()); 910 ++Index; 911 return; 912 } 913 ExprRes.release(); 914 // Fall through for subaggregate initialization 915 } 916 917 // C++ [dcl.init.aggr]p12: 918 // 919 // [...] Otherwise, if the member is itself a non-empty 920 // subaggregate, brace elision is assumed and the initializer is 921 // considered for the initialization of the first member of 922 // the subaggregate. 923 if (!SemaRef.getLangOpts().OpenCL && 924 (ElemType->isAggregateType() || ElemType->isVectorType())) { 925 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList, 926 StructuredIndex); 927 ++StructuredIndex; 928 } else { 929 if (!VerifyOnly) { 930 // We cannot initialize this element, so let 931 // PerformCopyInitialization produce the appropriate diagnostic. 932 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), 933 SemaRef.Owned(expr), 934 /*TopLevelOfInitList=*/true); 935 } 936 hadError = true; 937 ++Index; 938 ++StructuredIndex; 939 } 940} 941 942void InitListChecker::CheckComplexType(const InitializedEntity &Entity, 943 InitListExpr *IList, QualType DeclType, 944 unsigned &Index, 945 InitListExpr *StructuredList, 946 unsigned &StructuredIndex) { 947 assert(Index == 0 && "Index in explicit init list must be zero"); 948 949 // As an extension, clang supports complex initializers, which initialize 950 // a complex number component-wise. When an explicit initializer list for 951 // a complex number contains two two initializers, this extension kicks in: 952 // it exepcts the initializer list to contain two elements convertible to 953 // the element type of the complex type. The first element initializes 954 // the real part, and the second element intitializes the imaginary part. 955 956 if (IList->getNumInits() != 2) 957 return CheckScalarType(Entity, IList, DeclType, Index, StructuredList, 958 StructuredIndex); 959 960 // This is an extension in C. (The builtin _Complex type does not exist 961 // in the C++ standard.) 962 if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly) 963 SemaRef.Diag(IList->getLocStart(), diag::ext_complex_component_init) 964 << IList->getSourceRange(); 965 966 // Initialize the complex number. 967 QualType elementType = DeclType->getAs<ComplexType>()->getElementType(); 968 InitializedEntity ElementEntity = 969 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 970 971 for (unsigned i = 0; i < 2; ++i) { 972 ElementEntity.setElementIndex(Index); 973 CheckSubElementType(ElementEntity, IList, elementType, Index, 974 StructuredList, StructuredIndex); 975 } 976} 977 978 979void InitListChecker::CheckScalarType(const InitializedEntity &Entity, 980 InitListExpr *IList, QualType DeclType, 981 unsigned &Index, 982 InitListExpr *StructuredList, 983 unsigned &StructuredIndex) { 984 if (Index >= IList->getNumInits()) { 985 if (!VerifyOnly) 986 SemaRef.Diag(IList->getLocStart(), 987 SemaRef.getLangOpts().CPlusPlus11 ? 988 diag::warn_cxx98_compat_empty_scalar_initializer : 989 diag::err_empty_scalar_initializer) 990 << IList->getSourceRange(); 991 hadError = !SemaRef.getLangOpts().CPlusPlus11; 992 ++Index; 993 ++StructuredIndex; 994 return; 995 } 996 997 Expr *expr = IList->getInit(Index); 998 if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) { 999 if (!VerifyOnly) 1000 SemaRef.Diag(SubIList->getLocStart(), 1001 diag::warn_many_braces_around_scalar_init) 1002 << SubIList->getSourceRange(); 1003 1004 CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList, 1005 StructuredIndex); 1006 return; 1007 } else if (isa<DesignatedInitExpr>(expr)) { 1008 if (!VerifyOnly) 1009 SemaRef.Diag(expr->getLocStart(), 1010 diag::err_designator_for_scalar_init) 1011 << DeclType << expr->getSourceRange(); 1012 hadError = true; 1013 ++Index; 1014 ++StructuredIndex; 1015 return; 1016 } 1017 1018 if (VerifyOnly) { 1019 if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(expr))) 1020 hadError = true; 1021 ++Index; 1022 return; 1023 } 1024 1025 ExprResult Result = 1026 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 1027 SemaRef.Owned(expr), 1028 /*TopLevelOfInitList=*/true); 1029 1030 Expr *ResultExpr = 0; 1031 1032 if (Result.isInvalid()) 1033 hadError = true; // types weren't compatible. 1034 else { 1035 ResultExpr = Result.takeAs<Expr>(); 1036 1037 if (ResultExpr != expr) { 1038 // The type was promoted, update initializer list. 1039 IList->setInit(Index, ResultExpr); 1040 } 1041 } 1042 if (hadError) 1043 ++StructuredIndex; 1044 else 1045 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr); 1046 ++Index; 1047} 1048 1049void InitListChecker::CheckReferenceType(const InitializedEntity &Entity, 1050 InitListExpr *IList, QualType DeclType, 1051 unsigned &Index, 1052 InitListExpr *StructuredList, 1053 unsigned &StructuredIndex) { 1054 if (Index >= IList->getNumInits()) { 1055 // FIXME: It would be wonderful if we could point at the actual member. In 1056 // general, it would be useful to pass location information down the stack, 1057 // so that we know the location (or decl) of the "current object" being 1058 // initialized. 1059 if (!VerifyOnly) 1060 SemaRef.Diag(IList->getLocStart(), 1061 diag::err_init_reference_member_uninitialized) 1062 << DeclType 1063 << IList->getSourceRange(); 1064 hadError = true; 1065 ++Index; 1066 ++StructuredIndex; 1067 return; 1068 } 1069 1070 Expr *expr = IList->getInit(Index); 1071 if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus11) { 1072 if (!VerifyOnly) 1073 SemaRef.Diag(IList->getLocStart(), diag::err_init_non_aggr_init_list) 1074 << DeclType << IList->getSourceRange(); 1075 hadError = true; 1076 ++Index; 1077 ++StructuredIndex; 1078 return; 1079 } 1080 1081 if (VerifyOnly) { 1082 if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(expr))) 1083 hadError = true; 1084 ++Index; 1085 return; 1086 } 1087 1088 ExprResult Result = 1089 SemaRef.PerformCopyInitialization(Entity, expr->getLocStart(), 1090 SemaRef.Owned(expr), 1091 /*TopLevelOfInitList=*/true); 1092 1093 if (Result.isInvalid()) 1094 hadError = true; 1095 1096 expr = Result.takeAs<Expr>(); 1097 IList->setInit(Index, expr); 1098 1099 if (hadError) 1100 ++StructuredIndex; 1101 else 1102 UpdateStructuredListElement(StructuredList, StructuredIndex, expr); 1103 ++Index; 1104} 1105 1106void InitListChecker::CheckVectorType(const InitializedEntity &Entity, 1107 InitListExpr *IList, QualType DeclType, 1108 unsigned &Index, 1109 InitListExpr *StructuredList, 1110 unsigned &StructuredIndex) { 1111 const VectorType *VT = DeclType->getAs<VectorType>(); 1112 unsigned maxElements = VT->getNumElements(); 1113 unsigned numEltsInit = 0; 1114 QualType elementType = VT->getElementType(); 1115 1116 if (Index >= IList->getNumInits()) { 1117 // Make sure the element type can be value-initialized. 1118 if (VerifyOnly) 1119 CheckValueInitializable( 1120 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity)); 1121 return; 1122 } 1123 1124 if (!SemaRef.getLangOpts().OpenCL) { 1125 // If the initializing element is a vector, try to copy-initialize 1126 // instead of breaking it apart (which is doomed to failure anyway). 1127 Expr *Init = IList->getInit(Index); 1128 if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) { 1129 if (VerifyOnly) { 1130 if (!SemaRef.CanPerformCopyInitialization(Entity, SemaRef.Owned(Init))) 1131 hadError = true; 1132 ++Index; 1133 return; 1134 } 1135 1136 ExprResult Result = 1137 SemaRef.PerformCopyInitialization(Entity, Init->getLocStart(), 1138 SemaRef.Owned(Init), 1139 /*TopLevelOfInitList=*/true); 1140 1141 Expr *ResultExpr = 0; 1142 if (Result.isInvalid()) 1143 hadError = true; // types weren't compatible. 1144 else { 1145 ResultExpr = Result.takeAs<Expr>(); 1146 1147 if (ResultExpr != Init) { 1148 // The type was promoted, update initializer list. 1149 IList->setInit(Index, ResultExpr); 1150 } 1151 } 1152 if (hadError) 1153 ++StructuredIndex; 1154 else 1155 UpdateStructuredListElement(StructuredList, StructuredIndex, 1156 ResultExpr); 1157 ++Index; 1158 return; 1159 } 1160 1161 InitializedEntity ElementEntity = 1162 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 1163 1164 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) { 1165 // Don't attempt to go past the end of the init list 1166 if (Index >= IList->getNumInits()) { 1167 if (VerifyOnly) 1168 CheckValueInitializable(ElementEntity); 1169 break; 1170 } 1171 1172 ElementEntity.setElementIndex(Index); 1173 CheckSubElementType(ElementEntity, IList, elementType, Index, 1174 StructuredList, StructuredIndex); 1175 } 1176 return; 1177 } 1178 1179 InitializedEntity ElementEntity = 1180 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 1181 1182 // OpenCL initializers allows vectors to be constructed from vectors. 1183 for (unsigned i = 0; i < maxElements; ++i) { 1184 // Don't attempt to go past the end of the init list 1185 if (Index >= IList->getNumInits()) 1186 break; 1187 1188 ElementEntity.setElementIndex(Index); 1189 1190 QualType IType = IList->getInit(Index)->getType(); 1191 if (!IType->isVectorType()) { 1192 CheckSubElementType(ElementEntity, IList, elementType, Index, 1193 StructuredList, StructuredIndex); 1194 ++numEltsInit; 1195 } else { 1196 QualType VecType; 1197 const VectorType *IVT = IType->getAs<VectorType>(); 1198 unsigned numIElts = IVT->getNumElements(); 1199 1200 if (IType->isExtVectorType()) 1201 VecType = SemaRef.Context.getExtVectorType(elementType, numIElts); 1202 else 1203 VecType = SemaRef.Context.getVectorType(elementType, numIElts, 1204 IVT->getVectorKind()); 1205 CheckSubElementType(ElementEntity, IList, VecType, Index, 1206 StructuredList, StructuredIndex); 1207 numEltsInit += numIElts; 1208 } 1209 } 1210 1211 // OpenCL requires all elements to be initialized. 1212 if (numEltsInit != maxElements) { 1213 if (!VerifyOnly) 1214 SemaRef.Diag(IList->getLocStart(), 1215 diag::err_vector_incorrect_num_initializers) 1216 << (numEltsInit < maxElements) << maxElements << numEltsInit; 1217 hadError = true; 1218 } 1219} 1220 1221void InitListChecker::CheckArrayType(const InitializedEntity &Entity, 1222 InitListExpr *IList, QualType &DeclType, 1223 llvm::APSInt elementIndex, 1224 bool SubobjectIsDesignatorContext, 1225 unsigned &Index, 1226 InitListExpr *StructuredList, 1227 unsigned &StructuredIndex) { 1228 const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType); 1229 1230 // Check for the special-case of initializing an array with a string. 1231 if (Index < IList->getNumInits()) { 1232 if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) == 1233 SIF_None) { 1234 // We place the string literal directly into the resulting 1235 // initializer list. This is the only place where the structure 1236 // of the structured initializer list doesn't match exactly, 1237 // because doing so would involve allocating one character 1238 // constant for each string. 1239 if (!VerifyOnly) { 1240 CheckStringInit(IList->getInit(Index), DeclType, arrayType, SemaRef); 1241 UpdateStructuredListElement(StructuredList, StructuredIndex, 1242 IList->getInit(Index)); 1243 StructuredList->resizeInits(SemaRef.Context, StructuredIndex); 1244 } 1245 ++Index; 1246 return; 1247 } 1248 } 1249 if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) { 1250 // Check for VLAs; in standard C it would be possible to check this 1251 // earlier, but I don't know where clang accepts VLAs (gcc accepts 1252 // them in all sorts of strange places). 1253 if (!VerifyOnly) 1254 SemaRef.Diag(VAT->getSizeExpr()->getLocStart(), 1255 diag::err_variable_object_no_init) 1256 << VAT->getSizeExpr()->getSourceRange(); 1257 hadError = true; 1258 ++Index; 1259 ++StructuredIndex; 1260 return; 1261 } 1262 1263 // We might know the maximum number of elements in advance. 1264 llvm::APSInt maxElements(elementIndex.getBitWidth(), 1265 elementIndex.isUnsigned()); 1266 bool maxElementsKnown = false; 1267 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) { 1268 maxElements = CAT->getSize(); 1269 elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth()); 1270 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 1271 maxElementsKnown = true; 1272 } 1273 1274 QualType elementType = arrayType->getElementType(); 1275 while (Index < IList->getNumInits()) { 1276 Expr *Init = IList->getInit(Index); 1277 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 1278 // If we're not the subobject that matches up with the '{' for 1279 // the designator, we shouldn't be handling the 1280 // designator. Return immediately. 1281 if (!SubobjectIsDesignatorContext) 1282 return; 1283 1284 // Handle this designated initializer. elementIndex will be 1285 // updated to be the next array element we'll initialize. 1286 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 1287 DeclType, 0, &elementIndex, Index, 1288 StructuredList, StructuredIndex, true, 1289 false)) { 1290 hadError = true; 1291 continue; 1292 } 1293 1294 if (elementIndex.getBitWidth() > maxElements.getBitWidth()) 1295 maxElements = maxElements.extend(elementIndex.getBitWidth()); 1296 else if (elementIndex.getBitWidth() < maxElements.getBitWidth()) 1297 elementIndex = elementIndex.extend(maxElements.getBitWidth()); 1298 elementIndex.setIsUnsigned(maxElements.isUnsigned()); 1299 1300 // If the array is of incomplete type, keep track of the number of 1301 // elements in the initializer. 1302 if (!maxElementsKnown && elementIndex > maxElements) 1303 maxElements = elementIndex; 1304 1305 continue; 1306 } 1307 1308 // If we know the maximum number of elements, and we've already 1309 // hit it, stop consuming elements in the initializer list. 1310 if (maxElementsKnown && elementIndex == maxElements) 1311 break; 1312 1313 InitializedEntity ElementEntity = 1314 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex, 1315 Entity); 1316 // Check this element. 1317 CheckSubElementType(ElementEntity, IList, elementType, Index, 1318 StructuredList, StructuredIndex); 1319 ++elementIndex; 1320 1321 // If the array is of incomplete type, keep track of the number of 1322 // elements in the initializer. 1323 if (!maxElementsKnown && elementIndex > maxElements) 1324 maxElements = elementIndex; 1325 } 1326 if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) { 1327 // If this is an incomplete array type, the actual type needs to 1328 // be calculated here. 1329 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned()); 1330 if (maxElements == Zero) { 1331 // Sizing an array implicitly to zero is not allowed by ISO C, 1332 // but is supported by GNU. 1333 SemaRef.Diag(IList->getLocStart(), 1334 diag::ext_typecheck_zero_array_size); 1335 } 1336 1337 DeclType = SemaRef.Context.getConstantArrayType(elementType, maxElements, 1338 ArrayType::Normal, 0); 1339 } 1340 if (!hadError && VerifyOnly) { 1341 // Check if there are any members of the array that get value-initialized. 1342 // If so, check if doing that is possible. 1343 // FIXME: This needs to detect holes left by designated initializers too. 1344 if (maxElementsKnown && elementIndex < maxElements) 1345 CheckValueInitializable(InitializedEntity::InitializeElement( 1346 SemaRef.Context, 0, Entity)); 1347 } 1348} 1349 1350bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity, 1351 Expr *InitExpr, 1352 FieldDecl *Field, 1353 bool TopLevelObject) { 1354 // Handle GNU flexible array initializers. 1355 unsigned FlexArrayDiag; 1356 if (isa<InitListExpr>(InitExpr) && 1357 cast<InitListExpr>(InitExpr)->getNumInits() == 0) { 1358 // Empty flexible array init always allowed as an extension 1359 FlexArrayDiag = diag::ext_flexible_array_init; 1360 } else if (SemaRef.getLangOpts().CPlusPlus) { 1361 // Disallow flexible array init in C++; it is not required for gcc 1362 // compatibility, and it needs work to IRGen correctly in general. 1363 FlexArrayDiag = diag::err_flexible_array_init; 1364 } else if (!TopLevelObject) { 1365 // Disallow flexible array init on non-top-level object 1366 FlexArrayDiag = diag::err_flexible_array_init; 1367 } else if (Entity.getKind() != InitializedEntity::EK_Variable) { 1368 // Disallow flexible array init on anything which is not a variable. 1369 FlexArrayDiag = diag::err_flexible_array_init; 1370 } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) { 1371 // Disallow flexible array init on local variables. 1372 FlexArrayDiag = diag::err_flexible_array_init; 1373 } else { 1374 // Allow other cases. 1375 FlexArrayDiag = diag::ext_flexible_array_init; 1376 } 1377 1378 if (!VerifyOnly) { 1379 SemaRef.Diag(InitExpr->getLocStart(), 1380 FlexArrayDiag) 1381 << InitExpr->getLocStart(); 1382 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1383 << Field; 1384 } 1385 1386 return FlexArrayDiag != diag::ext_flexible_array_init; 1387} 1388 1389void InitListChecker::CheckStructUnionTypes(const InitializedEntity &Entity, 1390 InitListExpr *IList, 1391 QualType DeclType, 1392 RecordDecl::field_iterator Field, 1393 bool SubobjectIsDesignatorContext, 1394 unsigned &Index, 1395 InitListExpr *StructuredList, 1396 unsigned &StructuredIndex, 1397 bool TopLevelObject) { 1398 RecordDecl* structDecl = DeclType->getAs<RecordType>()->getDecl(); 1399 1400 // If the record is invalid, some of it's members are invalid. To avoid 1401 // confusion, we forgo checking the intializer for the entire record. 1402 if (structDecl->isInvalidDecl()) { 1403 // Assume it was supposed to consume a single initializer. 1404 ++Index; 1405 hadError = true; 1406 return; 1407 } 1408 1409 if (DeclType->isUnionType() && IList->getNumInits() == 0) { 1410 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1411 1412 // If there's a default initializer, use it. 1413 if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->hasInClassInitializer()) { 1414 if (VerifyOnly) 1415 return; 1416 for (RecordDecl::field_iterator FieldEnd = RD->field_end(); 1417 Field != FieldEnd; ++Field) { 1418 if (Field->hasInClassInitializer()) { 1419 StructuredList->setInitializedFieldInUnion(*Field); 1420 // FIXME: Actually build a CXXDefaultInitExpr? 1421 return; 1422 } 1423 } 1424 } 1425 1426 // Value-initialize the first named member of the union. 1427 for (RecordDecl::field_iterator FieldEnd = RD->field_end(); 1428 Field != FieldEnd; ++Field) { 1429 if (Field->getDeclName()) { 1430 if (VerifyOnly) 1431 CheckValueInitializable( 1432 InitializedEntity::InitializeMember(*Field, &Entity)); 1433 else 1434 StructuredList->setInitializedFieldInUnion(*Field); 1435 break; 1436 } 1437 } 1438 return; 1439 } 1440 1441 // If structDecl is a forward declaration, this loop won't do 1442 // anything except look at designated initializers; That's okay, 1443 // because an error should get printed out elsewhere. It might be 1444 // worthwhile to skip over the rest of the initializer, though. 1445 RecordDecl *RD = DeclType->getAs<RecordType>()->getDecl(); 1446 RecordDecl::field_iterator FieldEnd = RD->field_end(); 1447 bool InitializedSomething = false; 1448 bool CheckForMissingFields = true; 1449 while (Index < IList->getNumInits()) { 1450 Expr *Init = IList->getInit(Index); 1451 1452 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) { 1453 // If we're not the subobject that matches up with the '{' for 1454 // the designator, we shouldn't be handling the 1455 // designator. Return immediately. 1456 if (!SubobjectIsDesignatorContext) 1457 return; 1458 1459 // Handle this designated initializer. Field will be updated to 1460 // the next field that we'll be initializing. 1461 if (CheckDesignatedInitializer(Entity, IList, DIE, 0, 1462 DeclType, &Field, 0, Index, 1463 StructuredList, StructuredIndex, 1464 true, TopLevelObject)) 1465 hadError = true; 1466 1467 InitializedSomething = true; 1468 1469 // Disable check for missing fields when designators are used. 1470 // This matches gcc behaviour. 1471 CheckForMissingFields = false; 1472 continue; 1473 } 1474 1475 if (Field == FieldEnd) { 1476 // We've run out of fields. We're done. 1477 break; 1478 } 1479 1480 // We've already initialized a member of a union. We're done. 1481 if (InitializedSomething && DeclType->isUnionType()) 1482 break; 1483 1484 // If we've hit the flexible array member at the end, we're done. 1485 if (Field->getType()->isIncompleteArrayType()) 1486 break; 1487 1488 if (Field->isUnnamedBitfield()) { 1489 // Don't initialize unnamed bitfields, e.g. "int : 20;" 1490 ++Field; 1491 continue; 1492 } 1493 1494 // Make sure we can use this declaration. 1495 bool InvalidUse; 1496 if (VerifyOnly) 1497 InvalidUse = !SemaRef.CanUseDecl(*Field); 1498 else 1499 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, 1500 IList->getInit(Index)->getLocStart()); 1501 if (InvalidUse) { 1502 ++Index; 1503 ++Field; 1504 hadError = true; 1505 continue; 1506 } 1507 1508 InitializedEntity MemberEntity = 1509 InitializedEntity::InitializeMember(*Field, &Entity); 1510 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1511 StructuredList, StructuredIndex); 1512 InitializedSomething = true; 1513 1514 if (DeclType->isUnionType() && !VerifyOnly) { 1515 // Initialize the first field within the union. 1516 StructuredList->setInitializedFieldInUnion(*Field); 1517 } 1518 1519 ++Field; 1520 } 1521 1522 // Emit warnings for missing struct field initializers. 1523 if (!VerifyOnly && InitializedSomething && CheckForMissingFields && 1524 Field != FieldEnd && !Field->getType()->isIncompleteArrayType() && 1525 !DeclType->isUnionType()) { 1526 // It is possible we have one or more unnamed bitfields remaining. 1527 // Find first (if any) named field and emit warning. 1528 for (RecordDecl::field_iterator it = Field, end = RD->field_end(); 1529 it != end; ++it) { 1530 if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) { 1531 SemaRef.Diag(IList->getSourceRange().getEnd(), 1532 diag::warn_missing_field_initializers) << it->getName(); 1533 break; 1534 } 1535 } 1536 } 1537 1538 // Check that any remaining fields can be value-initialized. 1539 if (VerifyOnly && Field != FieldEnd && !DeclType->isUnionType() && 1540 !Field->getType()->isIncompleteArrayType()) { 1541 // FIXME: Should check for holes left by designated initializers too. 1542 for (; Field != FieldEnd && !hadError; ++Field) { 1543 if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer()) 1544 CheckValueInitializable( 1545 InitializedEntity::InitializeMember(*Field, &Entity)); 1546 } 1547 } 1548 1549 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() || 1550 Index >= IList->getNumInits()) 1551 return; 1552 1553 if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field, 1554 TopLevelObject)) { 1555 hadError = true; 1556 ++Index; 1557 return; 1558 } 1559 1560 InitializedEntity MemberEntity = 1561 InitializedEntity::InitializeMember(*Field, &Entity); 1562 1563 if (isa<InitListExpr>(IList->getInit(Index))) 1564 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1565 StructuredList, StructuredIndex); 1566 else 1567 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index, 1568 StructuredList, StructuredIndex); 1569} 1570 1571/// \brief Expand a field designator that refers to a member of an 1572/// anonymous struct or union into a series of field designators that 1573/// refers to the field within the appropriate subobject. 1574/// 1575static void ExpandAnonymousFieldDesignator(Sema &SemaRef, 1576 DesignatedInitExpr *DIE, 1577 unsigned DesigIdx, 1578 IndirectFieldDecl *IndirectField) { 1579 typedef DesignatedInitExpr::Designator Designator; 1580 1581 // Build the replacement designators. 1582 SmallVector<Designator, 4> Replacements; 1583 for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(), 1584 PE = IndirectField->chain_end(); PI != PE; ++PI) { 1585 if (PI + 1 == PE) 1586 Replacements.push_back(Designator((IdentifierInfo *)0, 1587 DIE->getDesignator(DesigIdx)->getDotLoc(), 1588 DIE->getDesignator(DesigIdx)->getFieldLoc())); 1589 else 1590 Replacements.push_back(Designator((IdentifierInfo *)0, SourceLocation(), 1591 SourceLocation())); 1592 assert(isa<FieldDecl>(*PI)); 1593 Replacements.back().setField(cast<FieldDecl>(*PI)); 1594 } 1595 1596 // Expand the current designator into the set of replacement 1597 // designators, so we have a full subobject path down to where the 1598 // member of the anonymous struct/union is actually stored. 1599 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0], 1600 &Replacements[0] + Replacements.size()); 1601} 1602 1603/// \brief Given an implicit anonymous field, search the IndirectField that 1604/// corresponds to FieldName. 1605static IndirectFieldDecl *FindIndirectFieldDesignator(FieldDecl *AnonField, 1606 IdentifierInfo *FieldName) { 1607 if (!FieldName) 1608 return 0; 1609 1610 assert(AnonField->isAnonymousStructOrUnion()); 1611 Decl *NextDecl = AnonField->getNextDeclInContext(); 1612 while (IndirectFieldDecl *IF = 1613 dyn_cast_or_null<IndirectFieldDecl>(NextDecl)) { 1614 if (FieldName == IF->getAnonField()->getIdentifier()) 1615 return IF; 1616 NextDecl = NextDecl->getNextDeclInContext(); 1617 } 1618 return 0; 1619} 1620 1621static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef, 1622 DesignatedInitExpr *DIE) { 1623 unsigned NumIndexExprs = DIE->getNumSubExprs() - 1; 1624 SmallVector<Expr*, 4> IndexExprs(NumIndexExprs); 1625 for (unsigned I = 0; I < NumIndexExprs; ++I) 1626 IndexExprs[I] = DIE->getSubExpr(I + 1); 1627 return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators_begin(), 1628 DIE->size(), IndexExprs, 1629 DIE->getEqualOrColonLoc(), 1630 DIE->usesGNUSyntax(), DIE->getInit()); 1631} 1632 1633namespace { 1634 1635// Callback to only accept typo corrections that are for field members of 1636// the given struct or union. 1637class FieldInitializerValidatorCCC : public CorrectionCandidateCallback { 1638 public: 1639 explicit FieldInitializerValidatorCCC(RecordDecl *RD) 1640 : Record(RD) {} 1641 1642 virtual bool ValidateCandidate(const TypoCorrection &candidate) { 1643 FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>(); 1644 return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record); 1645 } 1646 1647 private: 1648 RecordDecl *Record; 1649}; 1650 1651} 1652 1653/// @brief Check the well-formedness of a C99 designated initializer. 1654/// 1655/// Determines whether the designated initializer @p DIE, which 1656/// resides at the given @p Index within the initializer list @p 1657/// IList, is well-formed for a current object of type @p DeclType 1658/// (C99 6.7.8). The actual subobject that this designator refers to 1659/// within the current subobject is returned in either 1660/// @p NextField or @p NextElementIndex (whichever is appropriate). 1661/// 1662/// @param IList The initializer list in which this designated 1663/// initializer occurs. 1664/// 1665/// @param DIE The designated initializer expression. 1666/// 1667/// @param DesigIdx The index of the current designator. 1668/// 1669/// @param CurrentObjectType The type of the "current object" (C99 6.7.8p17), 1670/// into which the designation in @p DIE should refer. 1671/// 1672/// @param NextField If non-NULL and the first designator in @p DIE is 1673/// a field, this will be set to the field declaration corresponding 1674/// to the field named by the designator. 1675/// 1676/// @param NextElementIndex If non-NULL and the first designator in @p 1677/// DIE is an array designator or GNU array-range designator, this 1678/// will be set to the last index initialized by this designator. 1679/// 1680/// @param Index Index into @p IList where the designated initializer 1681/// @p DIE occurs. 1682/// 1683/// @param StructuredList The initializer list expression that 1684/// describes all of the subobject initializers in the order they'll 1685/// actually be initialized. 1686/// 1687/// @returns true if there was an error, false otherwise. 1688bool 1689InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity, 1690 InitListExpr *IList, 1691 DesignatedInitExpr *DIE, 1692 unsigned DesigIdx, 1693 QualType &CurrentObjectType, 1694 RecordDecl::field_iterator *NextField, 1695 llvm::APSInt *NextElementIndex, 1696 unsigned &Index, 1697 InitListExpr *StructuredList, 1698 unsigned &StructuredIndex, 1699 bool FinishSubobjectInit, 1700 bool TopLevelObject) { 1701 if (DesigIdx == DIE->size()) { 1702 // Check the actual initialization for the designated object type. 1703 bool prevHadError = hadError; 1704 1705 // Temporarily remove the designator expression from the 1706 // initializer list that the child calls see, so that we don't try 1707 // to re-process the designator. 1708 unsigned OldIndex = Index; 1709 IList->setInit(OldIndex, DIE->getInit()); 1710 1711 CheckSubElementType(Entity, IList, CurrentObjectType, Index, 1712 StructuredList, StructuredIndex); 1713 1714 // Restore the designated initializer expression in the syntactic 1715 // form of the initializer list. 1716 if (IList->getInit(OldIndex) != DIE->getInit()) 1717 DIE->setInit(IList->getInit(OldIndex)); 1718 IList->setInit(OldIndex, DIE); 1719 1720 return hadError && !prevHadError; 1721 } 1722 1723 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx); 1724 bool IsFirstDesignator = (DesigIdx == 0); 1725 if (!VerifyOnly) { 1726 assert((IsFirstDesignator || StructuredList) && 1727 "Need a non-designated initializer list to start from"); 1728 1729 // Determine the structural initializer list that corresponds to the 1730 // current subobject. 1731 StructuredList = IsFirstDesignator? SyntacticToSemantic.lookup(IList) 1732 : getStructuredSubobjectInit(IList, Index, CurrentObjectType, 1733 StructuredList, StructuredIndex, 1734 SourceRange(D->getLocStart(), 1735 DIE->getLocEnd())); 1736 assert(StructuredList && "Expected a structured initializer list"); 1737 } 1738 1739 if (D->isFieldDesignator()) { 1740 // C99 6.7.8p7: 1741 // 1742 // If a designator has the form 1743 // 1744 // . identifier 1745 // 1746 // then the current object (defined below) shall have 1747 // structure or union type and the identifier shall be the 1748 // name of a member of that type. 1749 const RecordType *RT = CurrentObjectType->getAs<RecordType>(); 1750 if (!RT) { 1751 SourceLocation Loc = D->getDotLoc(); 1752 if (Loc.isInvalid()) 1753 Loc = D->getFieldLoc(); 1754 if (!VerifyOnly) 1755 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr) 1756 << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType; 1757 ++Index; 1758 return true; 1759 } 1760 1761 // Note: we perform a linear search of the fields here, despite 1762 // the fact that we have a faster lookup method, because we always 1763 // need to compute the field's index. 1764 FieldDecl *KnownField = D->getField(); 1765 IdentifierInfo *FieldName = D->getFieldName(); 1766 unsigned FieldIndex = 0; 1767 RecordDecl::field_iterator 1768 Field = RT->getDecl()->field_begin(), 1769 FieldEnd = RT->getDecl()->field_end(); 1770 for (; Field != FieldEnd; ++Field) { 1771 if (Field->isUnnamedBitfield()) 1772 continue; 1773 1774 // If we find a field representing an anonymous field, look in the 1775 // IndirectFieldDecl that follow for the designated initializer. 1776 if (!KnownField && Field->isAnonymousStructOrUnion()) { 1777 if (IndirectFieldDecl *IF = 1778 FindIndirectFieldDesignator(*Field, FieldName)) { 1779 // In verify mode, don't modify the original. 1780 if (VerifyOnly) 1781 DIE = CloneDesignatedInitExpr(SemaRef, DIE); 1782 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IF); 1783 D = DIE->getDesignator(DesigIdx); 1784 break; 1785 } 1786 } 1787 if (KnownField && KnownField == *Field) 1788 break; 1789 if (FieldName && FieldName == Field->getIdentifier()) 1790 break; 1791 1792 ++FieldIndex; 1793 } 1794 1795 if (Field == FieldEnd) { 1796 if (VerifyOnly) { 1797 ++Index; 1798 return true; // No typo correction when just trying this out. 1799 } 1800 1801 // There was no normal field in the struct with the designated 1802 // name. Perform another lookup for this name, which may find 1803 // something that we can't designate (e.g., a member function), 1804 // may find nothing, or may find a member of an anonymous 1805 // struct/union. 1806 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName); 1807 FieldDecl *ReplacementField = 0; 1808 if (Lookup.empty()) { 1809 // Name lookup didn't find anything. Determine whether this 1810 // was a typo for another field name. 1811 FieldInitializerValidatorCCC Validator(RT->getDecl()); 1812 TypoCorrection Corrected = SemaRef.CorrectTypo( 1813 DeclarationNameInfo(FieldName, D->getFieldLoc()), 1814 Sema::LookupMemberName, /*Scope=*/0, /*SS=*/0, Validator, 1815 RT->getDecl()); 1816 if (Corrected) { 1817 std::string CorrectedStr( 1818 Corrected.getAsString(SemaRef.getLangOpts())); 1819 std::string CorrectedQuotedStr( 1820 Corrected.getQuoted(SemaRef.getLangOpts())); 1821 ReplacementField = Corrected.getCorrectionDeclAs<FieldDecl>(); 1822 SemaRef.Diag(D->getFieldLoc(), 1823 diag::err_field_designator_unknown_suggest) 1824 << FieldName << CurrentObjectType << CorrectedQuotedStr 1825 << FixItHint::CreateReplacement(D->getFieldLoc(), CorrectedStr); 1826 SemaRef.Diag(ReplacementField->getLocation(), 1827 diag::note_previous_decl) << CorrectedQuotedStr; 1828 hadError = true; 1829 } else { 1830 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown) 1831 << FieldName << CurrentObjectType; 1832 ++Index; 1833 return true; 1834 } 1835 } 1836 1837 if (!ReplacementField) { 1838 // Name lookup found something, but it wasn't a field. 1839 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield) 1840 << FieldName; 1841 SemaRef.Diag(Lookup.front()->getLocation(), 1842 diag::note_field_designator_found); 1843 ++Index; 1844 return true; 1845 } 1846 1847 if (!KnownField) { 1848 // The replacement field comes from typo correction; find it 1849 // in the list of fields. 1850 FieldIndex = 0; 1851 Field = RT->getDecl()->field_begin(); 1852 for (; Field != FieldEnd; ++Field) { 1853 if (Field->isUnnamedBitfield()) 1854 continue; 1855 1856 if (ReplacementField == *Field || 1857 Field->getIdentifier() == ReplacementField->getIdentifier()) 1858 break; 1859 1860 ++FieldIndex; 1861 } 1862 } 1863 } 1864 1865 // All of the fields of a union are located at the same place in 1866 // the initializer list. 1867 if (RT->getDecl()->isUnion()) { 1868 FieldIndex = 0; 1869 if (!VerifyOnly) 1870 StructuredList->setInitializedFieldInUnion(*Field); 1871 } 1872 1873 // Make sure we can use this declaration. 1874 bool InvalidUse; 1875 if (VerifyOnly) 1876 InvalidUse = !SemaRef.CanUseDecl(*Field); 1877 else 1878 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc()); 1879 if (InvalidUse) { 1880 ++Index; 1881 return true; 1882 } 1883 1884 if (!VerifyOnly) { 1885 // Update the designator with the field declaration. 1886 D->setField(*Field); 1887 1888 // Make sure that our non-designated initializer list has space 1889 // for a subobject corresponding to this field. 1890 if (FieldIndex >= StructuredList->getNumInits()) 1891 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1); 1892 } 1893 1894 // This designator names a flexible array member. 1895 if (Field->getType()->isIncompleteArrayType()) { 1896 bool Invalid = false; 1897 if ((DesigIdx + 1) != DIE->size()) { 1898 // We can't designate an object within the flexible array 1899 // member (because GCC doesn't allow it). 1900 if (!VerifyOnly) { 1901 DesignatedInitExpr::Designator *NextD 1902 = DIE->getDesignator(DesigIdx + 1); 1903 SemaRef.Diag(NextD->getLocStart(), 1904 diag::err_designator_into_flexible_array_member) 1905 << SourceRange(NextD->getLocStart(), 1906 DIE->getLocEnd()); 1907 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1908 << *Field; 1909 } 1910 Invalid = true; 1911 } 1912 1913 if (!hadError && !isa<InitListExpr>(DIE->getInit()) && 1914 !isa<StringLiteral>(DIE->getInit())) { 1915 // The initializer is not an initializer list. 1916 if (!VerifyOnly) { 1917 SemaRef.Diag(DIE->getInit()->getLocStart(), 1918 diag::err_flexible_array_init_needs_braces) 1919 << DIE->getInit()->getSourceRange(); 1920 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member) 1921 << *Field; 1922 } 1923 Invalid = true; 1924 } 1925 1926 // Check GNU flexible array initializer. 1927 if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field, 1928 TopLevelObject)) 1929 Invalid = true; 1930 1931 if (Invalid) { 1932 ++Index; 1933 return true; 1934 } 1935 1936 // Initialize the array. 1937 bool prevHadError = hadError; 1938 unsigned newStructuredIndex = FieldIndex; 1939 unsigned OldIndex = Index; 1940 IList->setInit(Index, DIE->getInit()); 1941 1942 InitializedEntity MemberEntity = 1943 InitializedEntity::InitializeMember(*Field, &Entity); 1944 CheckSubElementType(MemberEntity, IList, Field->getType(), Index, 1945 StructuredList, newStructuredIndex); 1946 1947 IList->setInit(OldIndex, DIE); 1948 if (hadError && !prevHadError) { 1949 ++Field; 1950 ++FieldIndex; 1951 if (NextField) 1952 *NextField = Field; 1953 StructuredIndex = FieldIndex; 1954 return true; 1955 } 1956 } else { 1957 // Recurse to check later designated subobjects. 1958 QualType FieldType = Field->getType(); 1959 unsigned newStructuredIndex = FieldIndex; 1960 1961 InitializedEntity MemberEntity = 1962 InitializedEntity::InitializeMember(*Field, &Entity); 1963 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1, 1964 FieldType, 0, 0, Index, 1965 StructuredList, newStructuredIndex, 1966 true, false)) 1967 return true; 1968 } 1969 1970 // Find the position of the next field to be initialized in this 1971 // subobject. 1972 ++Field; 1973 ++FieldIndex; 1974 1975 // If this the first designator, our caller will continue checking 1976 // the rest of this struct/class/union subobject. 1977 if (IsFirstDesignator) { 1978 if (NextField) 1979 *NextField = Field; 1980 StructuredIndex = FieldIndex; 1981 return false; 1982 } 1983 1984 if (!FinishSubobjectInit) 1985 return false; 1986 1987 // We've already initialized something in the union; we're done. 1988 if (RT->getDecl()->isUnion()) 1989 return hadError; 1990 1991 // Check the remaining fields within this class/struct/union subobject. 1992 bool prevHadError = hadError; 1993 1994 CheckStructUnionTypes(Entity, IList, CurrentObjectType, Field, false, Index, 1995 StructuredList, FieldIndex); 1996 return hadError && !prevHadError; 1997 } 1998 1999 // C99 6.7.8p6: 2000 // 2001 // If a designator has the form 2002 // 2003 // [ constant-expression ] 2004 // 2005 // then the current object (defined below) shall have array 2006 // type and the expression shall be an integer constant 2007 // expression. If the array is of unknown size, any 2008 // nonnegative value is valid. 2009 // 2010 // Additionally, cope with the GNU extension that permits 2011 // designators of the form 2012 // 2013 // [ constant-expression ... constant-expression ] 2014 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType); 2015 if (!AT) { 2016 if (!VerifyOnly) 2017 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array) 2018 << CurrentObjectType; 2019 ++Index; 2020 return true; 2021 } 2022 2023 Expr *IndexExpr = 0; 2024 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex; 2025 if (D->isArrayDesignator()) { 2026 IndexExpr = DIE->getArrayIndex(*D); 2027 DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context); 2028 DesignatedEndIndex = DesignatedStartIndex; 2029 } else { 2030 assert(D->isArrayRangeDesignator() && "Need array-range designator"); 2031 2032 DesignatedStartIndex = 2033 DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context); 2034 DesignatedEndIndex = 2035 DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context); 2036 IndexExpr = DIE->getArrayRangeEnd(*D); 2037 2038 // Codegen can't handle evaluating array range designators that have side 2039 // effects, because we replicate the AST value for each initialized element. 2040 // As such, set the sawArrayRangeDesignator() bit if we initialize multiple 2041 // elements with something that has a side effect, so codegen can emit an 2042 // "error unsupported" error instead of miscompiling the app. 2043 if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&& 2044 DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly) 2045 FullyStructuredList->sawArrayRangeDesignator(); 2046 } 2047 2048 if (isa<ConstantArrayType>(AT)) { 2049 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false); 2050 DesignatedStartIndex 2051 = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth()); 2052 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned()); 2053 DesignatedEndIndex 2054 = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth()); 2055 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned()); 2056 if (DesignatedEndIndex >= MaxElements) { 2057 if (!VerifyOnly) 2058 SemaRef.Diag(IndexExpr->getLocStart(), 2059 diag::err_array_designator_too_large) 2060 << DesignatedEndIndex.toString(10) << MaxElements.toString(10) 2061 << IndexExpr->getSourceRange(); 2062 ++Index; 2063 return true; 2064 } 2065 } else { 2066 // Make sure the bit-widths and signedness match. 2067 if (DesignatedStartIndex.getBitWidth() > DesignatedEndIndex.getBitWidth()) 2068 DesignatedEndIndex 2069 = DesignatedEndIndex.extend(DesignatedStartIndex.getBitWidth()); 2070 else if (DesignatedStartIndex.getBitWidth() < 2071 DesignatedEndIndex.getBitWidth()) 2072 DesignatedStartIndex 2073 = DesignatedStartIndex.extend(DesignatedEndIndex.getBitWidth()); 2074 DesignatedStartIndex.setIsUnsigned(true); 2075 DesignatedEndIndex.setIsUnsigned(true); 2076 } 2077 2078 if (!VerifyOnly && StructuredList->isStringLiteralInit()) { 2079 // We're modifying a string literal init; we have to decompose the string 2080 // so we can modify the individual characters. 2081 ASTContext &Context = SemaRef.Context; 2082 Expr *SubExpr = StructuredList->getInit(0)->IgnoreParens(); 2083 2084 // Compute the character type 2085 QualType CharTy = AT->getElementType(); 2086 2087 // Compute the type of the integer literals. 2088 QualType PromotedCharTy = CharTy; 2089 if (CharTy->isPromotableIntegerType()) 2090 PromotedCharTy = Context.getPromotedIntegerType(CharTy); 2091 unsigned PromotedCharTyWidth = Context.getTypeSize(PromotedCharTy); 2092 2093 if (StringLiteral *SL = dyn_cast<StringLiteral>(SubExpr)) { 2094 // Get the length of the string. 2095 uint64_t StrLen = SL->getLength(); 2096 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen)) 2097 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue(); 2098 StructuredList->resizeInits(Context, StrLen); 2099 2100 // Build a literal for each character in the string, and put them into 2101 // the init list. 2102 for (unsigned i = 0, e = StrLen; i != e; ++i) { 2103 llvm::APInt CodeUnit(PromotedCharTyWidth, SL->getCodeUnit(i)); 2104 Expr *Init = new (Context) IntegerLiteral( 2105 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc()); 2106 if (CharTy != PromotedCharTy) 2107 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast, 2108 Init, 0, VK_RValue); 2109 StructuredList->updateInit(Context, i, Init); 2110 } 2111 } else { 2112 ObjCEncodeExpr *E = cast<ObjCEncodeExpr>(SubExpr); 2113 std::string Str; 2114 Context.getObjCEncodingForType(E->getEncodedType(), Str); 2115 2116 // Get the length of the string. 2117 uint64_t StrLen = Str.size(); 2118 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen)) 2119 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue(); 2120 StructuredList->resizeInits(Context, StrLen); 2121 2122 // Build a literal for each character in the string, and put them into 2123 // the init list. 2124 for (unsigned i = 0, e = StrLen; i != e; ++i) { 2125 llvm::APInt CodeUnit(PromotedCharTyWidth, Str[i]); 2126 Expr *Init = new (Context) IntegerLiteral( 2127 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc()); 2128 if (CharTy != PromotedCharTy) 2129 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast, 2130 Init, 0, VK_RValue); 2131 StructuredList->updateInit(Context, i, Init); 2132 } 2133 } 2134 } 2135 2136 // Make sure that our non-designated initializer list has space 2137 // for a subobject corresponding to this array element. 2138 if (!VerifyOnly && 2139 DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits()) 2140 StructuredList->resizeInits(SemaRef.Context, 2141 DesignatedEndIndex.getZExtValue() + 1); 2142 2143 // Repeatedly perform subobject initializations in the range 2144 // [DesignatedStartIndex, DesignatedEndIndex]. 2145 2146 // Move to the next designator 2147 unsigned ElementIndex = DesignatedStartIndex.getZExtValue(); 2148 unsigned OldIndex = Index; 2149 2150 InitializedEntity ElementEntity = 2151 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity); 2152 2153 while (DesignatedStartIndex <= DesignatedEndIndex) { 2154 // Recurse to check later designated subobjects. 2155 QualType ElementType = AT->getElementType(); 2156 Index = OldIndex; 2157 2158 ElementEntity.setElementIndex(ElementIndex); 2159 if (CheckDesignatedInitializer(ElementEntity, IList, DIE, DesigIdx + 1, 2160 ElementType, 0, 0, Index, 2161 StructuredList, ElementIndex, 2162 (DesignatedStartIndex == DesignatedEndIndex), 2163 false)) 2164 return true; 2165 2166 // Move to the next index in the array that we'll be initializing. 2167 ++DesignatedStartIndex; 2168 ElementIndex = DesignatedStartIndex.getZExtValue(); 2169 } 2170 2171 // If this the first designator, our caller will continue checking 2172 // the rest of this array subobject. 2173 if (IsFirstDesignator) { 2174 if (NextElementIndex) 2175 *NextElementIndex = DesignatedStartIndex; 2176 StructuredIndex = ElementIndex; 2177 return false; 2178 } 2179 2180 if (!FinishSubobjectInit) 2181 return false; 2182 2183 // Check the remaining elements within this array subobject. 2184 bool prevHadError = hadError; 2185 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex, 2186 /*SubobjectIsDesignatorContext=*/false, Index, 2187 StructuredList, ElementIndex); 2188 return hadError && !prevHadError; 2189} 2190 2191// Get the structured initializer list for a subobject of type 2192// @p CurrentObjectType. 2193InitListExpr * 2194InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index, 2195 QualType CurrentObjectType, 2196 InitListExpr *StructuredList, 2197 unsigned StructuredIndex, 2198 SourceRange InitRange) { 2199 if (VerifyOnly) 2200 return 0; // No structured list in verification-only mode. 2201 Expr *ExistingInit = 0; 2202 if (!StructuredList) 2203 ExistingInit = SyntacticToSemantic.lookup(IList); 2204 else if (StructuredIndex < StructuredList->getNumInits()) 2205 ExistingInit = StructuredList->getInit(StructuredIndex); 2206 2207 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit)) 2208 return Result; 2209 2210 if (ExistingInit) { 2211 // We are creating an initializer list that initializes the 2212 // subobjects of the current object, but there was already an 2213 // initialization that completely initialized the current 2214 // subobject, e.g., by a compound literal: 2215 // 2216 // struct X { int a, b; }; 2217 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 }; 2218 // 2219 // Here, xs[0].a == 0 and xs[0].b == 3, since the second, 2220 // designated initializer re-initializes the whole 2221 // subobject [0], overwriting previous initializers. 2222 SemaRef.Diag(InitRange.getBegin(), 2223 diag::warn_subobject_initializer_overrides) 2224 << InitRange; 2225 SemaRef.Diag(ExistingInit->getLocStart(), 2226 diag::note_previous_initializer) 2227 << /*FIXME:has side effects=*/0 2228 << ExistingInit->getSourceRange(); 2229 } 2230 2231 InitListExpr *Result 2232 = new (SemaRef.Context) InitListExpr(SemaRef.Context, 2233 InitRange.getBegin(), None, 2234 InitRange.getEnd()); 2235 2236 QualType ResultType = CurrentObjectType; 2237 if (!ResultType->isArrayType()) 2238 ResultType = ResultType.getNonLValueExprType(SemaRef.Context); 2239 Result->setType(ResultType); 2240 2241 // Pre-allocate storage for the structured initializer list. 2242 unsigned NumElements = 0; 2243 unsigned NumInits = 0; 2244 bool GotNumInits = false; 2245 if (!StructuredList) { 2246 NumInits = IList->getNumInits(); 2247 GotNumInits = true; 2248 } else if (Index < IList->getNumInits()) { 2249 if (InitListExpr *SubList = dyn_cast<InitListExpr>(IList->getInit(Index))) { 2250 NumInits = SubList->getNumInits(); 2251 GotNumInits = true; 2252 } 2253 } 2254 2255 if (const ArrayType *AType 2256 = SemaRef.Context.getAsArrayType(CurrentObjectType)) { 2257 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) { 2258 NumElements = CAType->getSize().getZExtValue(); 2259 // Simple heuristic so that we don't allocate a very large 2260 // initializer with many empty entries at the end. 2261 if (GotNumInits && NumElements > NumInits) 2262 NumElements = 0; 2263 } 2264 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>()) 2265 NumElements = VType->getNumElements(); 2266 else if (const RecordType *RType = CurrentObjectType->getAs<RecordType>()) { 2267 RecordDecl *RDecl = RType->getDecl(); 2268 if (RDecl->isUnion()) 2269 NumElements = 1; 2270 else 2271 NumElements = std::distance(RDecl->field_begin(), 2272 RDecl->field_end()); 2273 } 2274 2275 Result->reserveInits(SemaRef.Context, NumElements); 2276 2277 // Link this new initializer list into the structured initializer 2278 // lists. 2279 if (StructuredList) 2280 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result); 2281 else { 2282 Result->setSyntacticForm(IList); 2283 SyntacticToSemantic[IList] = Result; 2284 } 2285 2286 return Result; 2287} 2288 2289/// Update the initializer at index @p StructuredIndex within the 2290/// structured initializer list to the value @p expr. 2291void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList, 2292 unsigned &StructuredIndex, 2293 Expr *expr) { 2294 // No structured initializer list to update 2295 if (!StructuredList) 2296 return; 2297 2298 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context, 2299 StructuredIndex, expr)) { 2300 // This initializer overwrites a previous initializer. Warn. 2301 SemaRef.Diag(expr->getLocStart(), 2302 diag::warn_initializer_overrides) 2303 << expr->getSourceRange(); 2304 SemaRef.Diag(PrevInit->getLocStart(), 2305 diag::note_previous_initializer) 2306 << /*FIXME:has side effects=*/0 2307 << PrevInit->getSourceRange(); 2308 } 2309 2310 ++StructuredIndex; 2311} 2312 2313/// Check that the given Index expression is a valid array designator 2314/// value. This is essentially just a wrapper around 2315/// VerifyIntegerConstantExpression that also checks for negative values 2316/// and produces a reasonable diagnostic if there is a 2317/// failure. Returns the index expression, possibly with an implicit cast 2318/// added, on success. If everything went okay, Value will receive the 2319/// value of the constant expression. 2320static ExprResult 2321CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) { 2322 SourceLocation Loc = Index->getLocStart(); 2323 2324 // Make sure this is an integer constant expression. 2325 ExprResult Result = S.VerifyIntegerConstantExpression(Index, &Value); 2326 if (Result.isInvalid()) 2327 return Result; 2328 2329 if (Value.isSigned() && Value.isNegative()) 2330 return S.Diag(Loc, diag::err_array_designator_negative) 2331 << Value.toString(10) << Index->getSourceRange(); 2332 2333 Value.setIsUnsigned(true); 2334 return Result; 2335} 2336 2337ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig, 2338 SourceLocation Loc, 2339 bool GNUSyntax, 2340 ExprResult Init) { 2341 typedef DesignatedInitExpr::Designator ASTDesignator; 2342 2343 bool Invalid = false; 2344 SmallVector<ASTDesignator, 32> Designators; 2345 SmallVector<Expr *, 32> InitExpressions; 2346 2347 // Build designators and check array designator expressions. 2348 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) { 2349 const Designator &D = Desig.getDesignator(Idx); 2350 switch (D.getKind()) { 2351 case Designator::FieldDesignator: 2352 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(), 2353 D.getFieldLoc())); 2354 break; 2355 2356 case Designator::ArrayDesignator: { 2357 Expr *Index = static_cast<Expr *>(D.getArrayIndex()); 2358 llvm::APSInt IndexValue; 2359 if (!Index->isTypeDependent() && !Index->isValueDependent()) 2360 Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).take(); 2361 if (!Index) 2362 Invalid = true; 2363 else { 2364 Designators.push_back(ASTDesignator(InitExpressions.size(), 2365 D.getLBracketLoc(), 2366 D.getRBracketLoc())); 2367 InitExpressions.push_back(Index); 2368 } 2369 break; 2370 } 2371 2372 case Designator::ArrayRangeDesignator: { 2373 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart()); 2374 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd()); 2375 llvm::APSInt StartValue; 2376 llvm::APSInt EndValue; 2377 bool StartDependent = StartIndex->isTypeDependent() || 2378 StartIndex->isValueDependent(); 2379 bool EndDependent = EndIndex->isTypeDependent() || 2380 EndIndex->isValueDependent(); 2381 if (!StartDependent) 2382 StartIndex = 2383 CheckArrayDesignatorExpr(*this, StartIndex, StartValue).take(); 2384 if (!EndDependent) 2385 EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).take(); 2386 2387 if (!StartIndex || !EndIndex) 2388 Invalid = true; 2389 else { 2390 // Make sure we're comparing values with the same bit width. 2391 if (StartDependent || EndDependent) { 2392 // Nothing to compute. 2393 } else if (StartValue.getBitWidth() > EndValue.getBitWidth()) 2394 EndValue = EndValue.extend(StartValue.getBitWidth()); 2395 else if (StartValue.getBitWidth() < EndValue.getBitWidth()) 2396 StartValue = StartValue.extend(EndValue.getBitWidth()); 2397 2398 if (!StartDependent && !EndDependent && EndValue < StartValue) { 2399 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range) 2400 << StartValue.toString(10) << EndValue.toString(10) 2401 << StartIndex->getSourceRange() << EndIndex->getSourceRange(); 2402 Invalid = true; 2403 } else { 2404 Designators.push_back(ASTDesignator(InitExpressions.size(), 2405 D.getLBracketLoc(), 2406 D.getEllipsisLoc(), 2407 D.getRBracketLoc())); 2408 InitExpressions.push_back(StartIndex); 2409 InitExpressions.push_back(EndIndex); 2410 } 2411 } 2412 break; 2413 } 2414 } 2415 } 2416 2417 if (Invalid || Init.isInvalid()) 2418 return ExprError(); 2419 2420 // Clear out the expressions within the designation. 2421 Desig.ClearExprs(*this); 2422 2423 DesignatedInitExpr *DIE 2424 = DesignatedInitExpr::Create(Context, 2425 Designators.data(), Designators.size(), 2426 InitExpressions, Loc, GNUSyntax, 2427 Init.takeAs<Expr>()); 2428 2429 if (!getLangOpts().C99) 2430 Diag(DIE->getLocStart(), diag::ext_designated_init) 2431 << DIE->getSourceRange(); 2432 2433 return Owned(DIE); 2434} 2435 2436//===----------------------------------------------------------------------===// 2437// Initialization entity 2438//===----------------------------------------------------------------------===// 2439 2440InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index, 2441 const InitializedEntity &Parent) 2442 : Parent(&Parent), Index(Index) 2443{ 2444 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) { 2445 Kind = EK_ArrayElement; 2446 Type = AT->getElementType(); 2447 } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) { 2448 Kind = EK_VectorElement; 2449 Type = VT->getElementType(); 2450 } else { 2451 const ComplexType *CT = Parent.getType()->getAs<ComplexType>(); 2452 assert(CT && "Unexpected type"); 2453 Kind = EK_ComplexElement; 2454 Type = CT->getElementType(); 2455 } 2456} 2457 2458InitializedEntity InitializedEntity::InitializeBase(ASTContext &Context, 2459 CXXBaseSpecifier *Base, 2460 bool IsInheritedVirtualBase) 2461{ 2462 InitializedEntity Result; 2463 Result.Kind = EK_Base; 2464 Result.Base = reinterpret_cast<uintptr_t>(Base); 2465 if (IsInheritedVirtualBase) 2466 Result.Base |= 0x01; 2467 2468 Result.Type = Base->getType(); 2469 return Result; 2470} 2471 2472DeclarationName InitializedEntity::getName() const { 2473 switch (getKind()) { 2474 case EK_Parameter: { 2475 ParmVarDecl *D = reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1); 2476 return (D ? D->getDeclName() : DeclarationName()); 2477 } 2478 2479 case EK_Variable: 2480 case EK_Member: 2481 return VariableOrMember->getDeclName(); 2482 2483 case EK_LambdaCapture: 2484 return Capture.Var->getDeclName(); 2485 2486 case EK_Result: 2487 case EK_Exception: 2488 case EK_New: 2489 case EK_Temporary: 2490 case EK_Base: 2491 case EK_Delegating: 2492 case EK_ArrayElement: 2493 case EK_VectorElement: 2494 case EK_ComplexElement: 2495 case EK_BlockElement: 2496 case EK_CompoundLiteralInit: 2497 return DeclarationName(); 2498 } 2499 2500 llvm_unreachable("Invalid EntityKind!"); 2501} 2502 2503DeclaratorDecl *InitializedEntity::getDecl() const { 2504 switch (getKind()) { 2505 case EK_Variable: 2506 case EK_Member: 2507 return VariableOrMember; 2508 2509 case EK_Parameter: 2510 return reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1); 2511 2512 case EK_Result: 2513 case EK_Exception: 2514 case EK_New: 2515 case EK_Temporary: 2516 case EK_Base: 2517 case EK_Delegating: 2518 case EK_ArrayElement: 2519 case EK_VectorElement: 2520 case EK_ComplexElement: 2521 case EK_BlockElement: 2522 case EK_LambdaCapture: 2523 case EK_CompoundLiteralInit: 2524 return 0; 2525 } 2526 2527 llvm_unreachable("Invalid EntityKind!"); 2528} 2529 2530bool InitializedEntity::allowsNRVO() const { 2531 switch (getKind()) { 2532 case EK_Result: 2533 case EK_Exception: 2534 return LocAndNRVO.NRVO; 2535 2536 case EK_Variable: 2537 case EK_Parameter: 2538 case EK_Member: 2539 case EK_New: 2540 case EK_Temporary: 2541 case EK_CompoundLiteralInit: 2542 case EK_Base: 2543 case EK_Delegating: 2544 case EK_ArrayElement: 2545 case EK_VectorElement: 2546 case EK_ComplexElement: 2547 case EK_BlockElement: 2548 case EK_LambdaCapture: 2549 break; 2550 } 2551 2552 return false; 2553} 2554 2555unsigned InitializedEntity::dumpImpl(raw_ostream &OS) const { 2556 unsigned Depth = getParent() ? getParent()->dumpImpl(OS) : 0; 2557 for (unsigned I = 0; I != Depth; ++I) 2558 OS << "`-"; 2559 2560 switch (getKind()) { 2561 case EK_Variable: OS << "Variable"; break; 2562 case EK_Parameter: OS << "Parameter"; break; 2563 case EK_Result: OS << "Result"; break; 2564 case EK_Exception: OS << "Exception"; break; 2565 case EK_Member: OS << "Member"; break; 2566 case EK_New: OS << "New"; break; 2567 case EK_Temporary: OS << "Temporary"; break; 2568 case EK_CompoundLiteralInit: OS << "CompoundLiteral";break; 2569 case EK_Base: OS << "Base"; break; 2570 case EK_Delegating: OS << "Delegating"; break; 2571 case EK_ArrayElement: OS << "ArrayElement " << Index; break; 2572 case EK_VectorElement: OS << "VectorElement " << Index; break; 2573 case EK_ComplexElement: OS << "ComplexElement " << Index; break; 2574 case EK_BlockElement: OS << "Block"; break; 2575 case EK_LambdaCapture: 2576 OS << "LambdaCapture "; 2577 getCapturedVar()->printName(OS); 2578 break; 2579 } 2580 2581 if (Decl *D = getDecl()) { 2582 OS << " "; 2583 cast<NamedDecl>(D)->printQualifiedName(OS); 2584 } 2585 2586 OS << " '" << getType().getAsString() << "'\n"; 2587 2588 return Depth + 1; 2589} 2590 2591void InitializedEntity::dump() const { 2592 dumpImpl(llvm::errs()); 2593} 2594 2595//===----------------------------------------------------------------------===// 2596// Initialization sequence 2597//===----------------------------------------------------------------------===// 2598 2599void InitializationSequence::Step::Destroy() { 2600 switch (Kind) { 2601 case SK_ResolveAddressOfOverloadedFunction: 2602 case SK_CastDerivedToBaseRValue: 2603 case SK_CastDerivedToBaseXValue: 2604 case SK_CastDerivedToBaseLValue: 2605 case SK_BindReference: 2606 case SK_BindReferenceToTemporary: 2607 case SK_ExtraneousCopyToTemporary: 2608 case SK_UserConversion: 2609 case SK_QualificationConversionRValue: 2610 case SK_QualificationConversionXValue: 2611 case SK_QualificationConversionLValue: 2612 case SK_LValueToRValue: 2613 case SK_ListInitialization: 2614 case SK_ListConstructorCall: 2615 case SK_UnwrapInitList: 2616 case SK_RewrapInitList: 2617 case SK_ConstructorInitialization: 2618 case SK_ZeroInitialization: 2619 case SK_CAssignment: 2620 case SK_StringInit: 2621 case SK_ObjCObjectConversion: 2622 case SK_ArrayInit: 2623 case SK_ParenthesizedArrayInit: 2624 case SK_PassByIndirectCopyRestore: 2625 case SK_PassByIndirectRestore: 2626 case SK_ProduceObjCObject: 2627 case SK_StdInitializerList: 2628 case SK_OCLSamplerInit: 2629 case SK_OCLZeroEvent: 2630 break; 2631 2632 case SK_ConversionSequence: 2633 delete ICS; 2634 } 2635} 2636 2637bool InitializationSequence::isDirectReferenceBinding() const { 2638 return !Steps.empty() && Steps.back().Kind == SK_BindReference; 2639} 2640 2641bool InitializationSequence::isAmbiguous() const { 2642 if (!Failed()) 2643 return false; 2644 2645 switch (getFailureKind()) { 2646 case FK_TooManyInitsForReference: 2647 case FK_ArrayNeedsInitList: 2648 case FK_ArrayNeedsInitListOrStringLiteral: 2649 case FK_ArrayNeedsInitListOrWideStringLiteral: 2650 case FK_NarrowStringIntoWideCharArray: 2651 case FK_WideStringIntoCharArray: 2652 case FK_IncompatWideStringIntoWideChar: 2653 case FK_AddressOfOverloadFailed: // FIXME: Could do better 2654 case FK_NonConstLValueReferenceBindingToTemporary: 2655 case FK_NonConstLValueReferenceBindingToUnrelated: 2656 case FK_RValueReferenceBindingToLValue: 2657 case FK_ReferenceInitDropsQualifiers: 2658 case FK_ReferenceInitFailed: 2659 case FK_ConversionFailed: 2660 case FK_ConversionFromPropertyFailed: 2661 case FK_TooManyInitsForScalar: 2662 case FK_ReferenceBindingToInitList: 2663 case FK_InitListBadDestinationType: 2664 case FK_DefaultInitOfConst: 2665 case FK_Incomplete: 2666 case FK_ArrayTypeMismatch: 2667 case FK_NonConstantArrayInit: 2668 case FK_ListInitializationFailed: 2669 case FK_VariableLengthArrayHasInitializer: 2670 case FK_PlaceholderType: 2671 case FK_InitListElementCopyFailure: 2672 case FK_ExplicitConstructor: 2673 return false; 2674 2675 case FK_ReferenceInitOverloadFailed: 2676 case FK_UserConversionOverloadFailed: 2677 case FK_ConstructorOverloadFailed: 2678 case FK_ListConstructorOverloadFailed: 2679 return FailedOverloadResult == OR_Ambiguous; 2680 } 2681 2682 llvm_unreachable("Invalid EntityKind!"); 2683} 2684 2685bool InitializationSequence::isConstructorInitialization() const { 2686 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization; 2687} 2688 2689void 2690InitializationSequence 2691::AddAddressOverloadResolutionStep(FunctionDecl *Function, 2692 DeclAccessPair Found, 2693 bool HadMultipleCandidates) { 2694 Step S; 2695 S.Kind = SK_ResolveAddressOfOverloadedFunction; 2696 S.Type = Function->getType(); 2697 S.Function.HadMultipleCandidates = HadMultipleCandidates; 2698 S.Function.Function = Function; 2699 S.Function.FoundDecl = Found; 2700 Steps.push_back(S); 2701} 2702 2703void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType, 2704 ExprValueKind VK) { 2705 Step S; 2706 switch (VK) { 2707 case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break; 2708 case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break; 2709 case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break; 2710 } 2711 S.Type = BaseType; 2712 Steps.push_back(S); 2713} 2714 2715void InitializationSequence::AddReferenceBindingStep(QualType T, 2716 bool BindingTemporary) { 2717 Step S; 2718 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference; 2719 S.Type = T; 2720 Steps.push_back(S); 2721} 2722 2723void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) { 2724 Step S; 2725 S.Kind = SK_ExtraneousCopyToTemporary; 2726 S.Type = T; 2727 Steps.push_back(S); 2728} 2729 2730void 2731InitializationSequence::AddUserConversionStep(FunctionDecl *Function, 2732 DeclAccessPair FoundDecl, 2733 QualType T, 2734 bool HadMultipleCandidates) { 2735 Step S; 2736 S.Kind = SK_UserConversion; 2737 S.Type = T; 2738 S.Function.HadMultipleCandidates = HadMultipleCandidates; 2739 S.Function.Function = Function; 2740 S.Function.FoundDecl = FoundDecl; 2741 Steps.push_back(S); 2742} 2743 2744void InitializationSequence::AddQualificationConversionStep(QualType Ty, 2745 ExprValueKind VK) { 2746 Step S; 2747 S.Kind = SK_QualificationConversionRValue; // work around a gcc warning 2748 switch (VK) { 2749 case VK_RValue: 2750 S.Kind = SK_QualificationConversionRValue; 2751 break; 2752 case VK_XValue: 2753 S.Kind = SK_QualificationConversionXValue; 2754 break; 2755 case VK_LValue: 2756 S.Kind = SK_QualificationConversionLValue; 2757 break; 2758 } 2759 S.Type = Ty; 2760 Steps.push_back(S); 2761} 2762 2763void InitializationSequence::AddLValueToRValueStep(QualType Ty) { 2764 assert(!Ty.hasQualifiers() && "rvalues may not have qualifiers"); 2765 2766 Step S; 2767 S.Kind = SK_LValueToRValue; 2768 S.Type = Ty; 2769 Steps.push_back(S); 2770} 2771 2772void InitializationSequence::AddConversionSequenceStep( 2773 const ImplicitConversionSequence &ICS, 2774 QualType T) { 2775 Step S; 2776 S.Kind = SK_ConversionSequence; 2777 S.Type = T; 2778 S.ICS = new ImplicitConversionSequence(ICS); 2779 Steps.push_back(S); 2780} 2781 2782void InitializationSequence::AddListInitializationStep(QualType T) { 2783 Step S; 2784 S.Kind = SK_ListInitialization; 2785 S.Type = T; 2786 Steps.push_back(S); 2787} 2788 2789void 2790InitializationSequence 2791::AddConstructorInitializationStep(CXXConstructorDecl *Constructor, 2792 AccessSpecifier Access, 2793 QualType T, 2794 bool HadMultipleCandidates, 2795 bool FromInitList, bool AsInitList) { 2796 Step S; 2797 S.Kind = FromInitList && !AsInitList ? SK_ListConstructorCall 2798 : SK_ConstructorInitialization; 2799 S.Type = T; 2800 S.Function.HadMultipleCandidates = HadMultipleCandidates; 2801 S.Function.Function = Constructor; 2802 S.Function.FoundDecl = DeclAccessPair::make(Constructor, Access); 2803 Steps.push_back(S); 2804} 2805 2806void InitializationSequence::AddZeroInitializationStep(QualType T) { 2807 Step S; 2808 S.Kind = SK_ZeroInitialization; 2809 S.Type = T; 2810 Steps.push_back(S); 2811} 2812 2813void InitializationSequence::AddCAssignmentStep(QualType T) { 2814 Step S; 2815 S.Kind = SK_CAssignment; 2816 S.Type = T; 2817 Steps.push_back(S); 2818} 2819 2820void InitializationSequence::AddStringInitStep(QualType T) { 2821 Step S; 2822 S.Kind = SK_StringInit; 2823 S.Type = T; 2824 Steps.push_back(S); 2825} 2826 2827void InitializationSequence::AddObjCObjectConversionStep(QualType T) { 2828 Step S; 2829 S.Kind = SK_ObjCObjectConversion; 2830 S.Type = T; 2831 Steps.push_back(S); 2832} 2833 2834void InitializationSequence::AddArrayInitStep(QualType T) { 2835 Step S; 2836 S.Kind = SK_ArrayInit; 2837 S.Type = T; 2838 Steps.push_back(S); 2839} 2840 2841void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) { 2842 Step S; 2843 S.Kind = SK_ParenthesizedArrayInit; 2844 S.Type = T; 2845 Steps.push_back(S); 2846} 2847 2848void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type, 2849 bool shouldCopy) { 2850 Step s; 2851 s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore 2852 : SK_PassByIndirectRestore); 2853 s.Type = type; 2854 Steps.push_back(s); 2855} 2856 2857void InitializationSequence::AddProduceObjCObjectStep(QualType T) { 2858 Step S; 2859 S.Kind = SK_ProduceObjCObject; 2860 S.Type = T; 2861 Steps.push_back(S); 2862} 2863 2864void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) { 2865 Step S; 2866 S.Kind = SK_StdInitializerList; 2867 S.Type = T; 2868 Steps.push_back(S); 2869} 2870 2871void InitializationSequence::AddOCLSamplerInitStep(QualType T) { 2872 Step S; 2873 S.Kind = SK_OCLSamplerInit; 2874 S.Type = T; 2875 Steps.push_back(S); 2876} 2877 2878void InitializationSequence::AddOCLZeroEventStep(QualType T) { 2879 Step S; 2880 S.Kind = SK_OCLZeroEvent; 2881 S.Type = T; 2882 Steps.push_back(S); 2883} 2884 2885void InitializationSequence::RewrapReferenceInitList(QualType T, 2886 InitListExpr *Syntactic) { 2887 assert(Syntactic->getNumInits() == 1 && 2888 "Can only rewrap trivial init lists."); 2889 Step S; 2890 S.Kind = SK_UnwrapInitList; 2891 S.Type = Syntactic->getInit(0)->getType(); 2892 Steps.insert(Steps.begin(), S); 2893 2894 S.Kind = SK_RewrapInitList; 2895 S.Type = T; 2896 S.WrappingSyntacticList = Syntactic; 2897 Steps.push_back(S); 2898} 2899 2900void InitializationSequence::SetOverloadFailure(FailureKind Failure, 2901 OverloadingResult Result) { 2902 setSequenceKind(FailedSequence); 2903 this->Failure = Failure; 2904 this->FailedOverloadResult = Result; 2905} 2906 2907//===----------------------------------------------------------------------===// 2908// Attempt initialization 2909//===----------------------------------------------------------------------===// 2910 2911static void MaybeProduceObjCObject(Sema &S, 2912 InitializationSequence &Sequence, 2913 const InitializedEntity &Entity) { 2914 if (!S.getLangOpts().ObjCAutoRefCount) return; 2915 2916 /// When initializing a parameter, produce the value if it's marked 2917 /// __attribute__((ns_consumed)). 2918 if (Entity.getKind() == InitializedEntity::EK_Parameter) { 2919 if (!Entity.isParameterConsumed()) 2920 return; 2921 2922 assert(Entity.getType()->isObjCRetainableType() && 2923 "consuming an object of unretainable type?"); 2924 Sequence.AddProduceObjCObjectStep(Entity.getType()); 2925 2926 /// When initializing a return value, if the return type is a 2927 /// retainable type, then returns need to immediately retain the 2928 /// object. If an autorelease is required, it will be done at the 2929 /// last instant. 2930 } else if (Entity.getKind() == InitializedEntity::EK_Result) { 2931 if (!Entity.getType()->isObjCRetainableType()) 2932 return; 2933 2934 Sequence.AddProduceObjCObjectStep(Entity.getType()); 2935 } 2936} 2937 2938/// \brief When initializing from init list via constructor, handle 2939/// initialization of an object of type std::initializer_list<T>. 2940/// 2941/// \return true if we have handled initialization of an object of type 2942/// std::initializer_list<T>, false otherwise. 2943static bool TryInitializerListConstruction(Sema &S, 2944 InitListExpr *List, 2945 QualType DestType, 2946 InitializationSequence &Sequence) { 2947 QualType E; 2948 if (!S.isStdInitializerList(DestType, &E)) 2949 return false; 2950 2951 // Check that each individual element can be copy-constructed. But since we 2952 // have no place to store further information, we'll recalculate everything 2953 // later. 2954 InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( 2955 S.Context.getConstantArrayType(E, 2956 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), 2957 List->getNumInits()), 2958 ArrayType::Normal, 0)); 2959 InitializedEntity Element = InitializedEntity::InitializeElement(S.Context, 2960 0, HiddenArray); 2961 for (unsigned i = 0, n = List->getNumInits(); i < n; ++i) { 2962 Element.setElementIndex(i); 2963 if (!S.CanPerformCopyInitialization(Element, List->getInit(i))) { 2964 Sequence.SetFailed( 2965 InitializationSequence::FK_InitListElementCopyFailure); 2966 return true; 2967 } 2968 } 2969 Sequence.AddStdInitializerListConstructionStep(DestType); 2970 return true; 2971} 2972 2973static OverloadingResult 2974ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc, 2975 MultiExprArg Args, 2976 OverloadCandidateSet &CandidateSet, 2977 ArrayRef<NamedDecl *> Ctors, 2978 OverloadCandidateSet::iterator &Best, 2979 bool CopyInitializing, bool AllowExplicit, 2980 bool OnlyListConstructors, bool InitListSyntax) { 2981 CandidateSet.clear(); 2982 2983 for (ArrayRef<NamedDecl *>::iterator 2984 Con = Ctors.begin(), ConEnd = Ctors.end(); Con != ConEnd; ++Con) { 2985 NamedDecl *D = *Con; 2986 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2987 bool SuppressUserConversions = false; 2988 2989 // Find the constructor (which may be a template). 2990 CXXConstructorDecl *Constructor = 0; 2991 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 2992 if (ConstructorTmpl) 2993 Constructor = cast<CXXConstructorDecl>( 2994 ConstructorTmpl->getTemplatedDecl()); 2995 else { 2996 Constructor = cast<CXXConstructorDecl>(D); 2997 2998 // If we're performing copy initialization using a copy constructor, we 2999 // suppress user-defined conversions on the arguments. We do the same for 3000 // move constructors. 3001 if ((CopyInitializing || (InitListSyntax && Args.size() == 1)) && 3002 Constructor->isCopyOrMoveConstructor()) 3003 SuppressUserConversions = true; 3004 } 3005 3006 if (!Constructor->isInvalidDecl() && 3007 (AllowExplicit || !Constructor->isExplicit()) && 3008 (!OnlyListConstructors || S.isInitListConstructor(Constructor))) { 3009 if (ConstructorTmpl) 3010 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 3011 /*ExplicitArgs*/ 0, Args, 3012 CandidateSet, SuppressUserConversions); 3013 else { 3014 // C++ [over.match.copy]p1: 3015 // - When initializing a temporary to be bound to the first parameter 3016 // of a constructor that takes a reference to possibly cv-qualified 3017 // T as its first argument, called with a single argument in the 3018 // context of direct-initialization, explicit conversion functions 3019 // are also considered. 3020 bool AllowExplicitConv = AllowExplicit && !CopyInitializing && 3021 Args.size() == 1 && 3022 Constructor->isCopyOrMoveConstructor(); 3023 S.AddOverloadCandidate(Constructor, FoundDecl, Args, CandidateSet, 3024 SuppressUserConversions, 3025 /*PartialOverloading=*/false, 3026 /*AllowExplicit=*/AllowExplicitConv); 3027 } 3028 } 3029 } 3030 3031 // Perform overload resolution and return the result. 3032 return CandidateSet.BestViableFunction(S, DeclLoc, Best); 3033} 3034 3035/// \brief Attempt initialization by constructor (C++ [dcl.init]), which 3036/// enumerates the constructors of the initialized entity and performs overload 3037/// resolution to select the best. 3038/// If InitListSyntax is true, this is list-initialization of a non-aggregate 3039/// class type. 3040static void TryConstructorInitialization(Sema &S, 3041 const InitializedEntity &Entity, 3042 const InitializationKind &Kind, 3043 MultiExprArg Args, QualType DestType, 3044 InitializationSequence &Sequence, 3045 bool InitListSyntax = false) { 3046 assert((!InitListSyntax || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && 3047 "InitListSyntax must come with a single initializer list argument."); 3048 3049 // The type we're constructing needs to be complete. 3050 if (S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { 3051 Sequence.setIncompleteTypeFailure(DestType); 3052 return; 3053 } 3054 3055 const RecordType *DestRecordType = DestType->getAs<RecordType>(); 3056 assert(DestRecordType && "Constructor initialization requires record type"); 3057 CXXRecordDecl *DestRecordDecl 3058 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 3059 3060 // Build the candidate set directly in the initialization sequence 3061 // structure, so that it will persist if we fail. 3062 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 3063 3064 // Determine whether we are allowed to call explicit constructors or 3065 // explicit conversion operators. 3066 bool AllowExplicit = Kind.AllowExplicit() || InitListSyntax; 3067 bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy; 3068 3069 // - Otherwise, if T is a class type, constructors are considered. The 3070 // applicable constructors are enumerated, and the best one is chosen 3071 // through overload resolution. 3072 DeclContext::lookup_result R = S.LookupConstructors(DestRecordDecl); 3073 // The container holding the constructors can under certain conditions 3074 // be changed while iterating (e.g. because of deserialization). 3075 // To be safe we copy the lookup results to a new container. 3076 SmallVector<NamedDecl*, 16> Ctors(R.begin(), R.end()); 3077 3078 OverloadingResult Result = OR_No_Viable_Function; 3079 OverloadCandidateSet::iterator Best; 3080 bool AsInitializerList = false; 3081 3082 // C++11 [over.match.list]p1: 3083 // When objects of non-aggregate type T are list-initialized, overload 3084 // resolution selects the constructor in two phases: 3085 // - Initially, the candidate functions are the initializer-list 3086 // constructors of the class T and the argument list consists of the 3087 // initializer list as a single argument. 3088 if (InitListSyntax) { 3089 InitListExpr *ILE = cast<InitListExpr>(Args[0]); 3090 AsInitializerList = true; 3091 3092 // If the initializer list has no elements and T has a default constructor, 3093 // the first phase is omitted. 3094 if (ILE->getNumInits() != 0 || !DestRecordDecl->hasDefaultConstructor()) 3095 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args, 3096 CandidateSet, Ctors, Best, 3097 CopyInitialization, AllowExplicit, 3098 /*OnlyListConstructor=*/true, 3099 InitListSyntax); 3100 3101 // Time to unwrap the init list. 3102 Args = MultiExprArg(ILE->getInits(), ILE->getNumInits()); 3103 } 3104 3105 // C++11 [over.match.list]p1: 3106 // - If no viable initializer-list constructor is found, overload resolution 3107 // is performed again, where the candidate functions are all the 3108 // constructors of the class T and the argument list consists of the 3109 // elements of the initializer list. 3110 if (Result == OR_No_Viable_Function) { 3111 AsInitializerList = false; 3112 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args, 3113 CandidateSet, Ctors, Best, 3114 CopyInitialization, AllowExplicit, 3115 /*OnlyListConstructors=*/false, 3116 InitListSyntax); 3117 } 3118 if (Result) { 3119 Sequence.SetOverloadFailure(InitListSyntax ? 3120 InitializationSequence::FK_ListConstructorOverloadFailed : 3121 InitializationSequence::FK_ConstructorOverloadFailed, 3122 Result); 3123 return; 3124 } 3125 3126 // C++11 [dcl.init]p6: 3127 // If a program calls for the default initialization of an object 3128 // of a const-qualified type T, T shall be a class type with a 3129 // user-provided default constructor. 3130 if (Kind.getKind() == InitializationKind::IK_Default && 3131 Entity.getType().isConstQualified() && 3132 !cast<CXXConstructorDecl>(Best->Function)->isUserProvided()) { 3133 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 3134 return; 3135 } 3136 3137 // C++11 [over.match.list]p1: 3138 // In copy-list-initialization, if an explicit constructor is chosen, the 3139 // initializer is ill-formed. 3140 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function); 3141 if (InitListSyntax && !Kind.AllowExplicit() && CtorDecl->isExplicit()) { 3142 Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor); 3143 return; 3144 } 3145 3146 // Add the constructor initialization step. Any cv-qualification conversion is 3147 // subsumed by the initialization. 3148 bool HadMultipleCandidates = (CandidateSet.size() > 1); 3149 Sequence.AddConstructorInitializationStep(CtorDecl, 3150 Best->FoundDecl.getAccess(), 3151 DestType, HadMultipleCandidates, 3152 InitListSyntax, AsInitializerList); 3153} 3154 3155static bool 3156ResolveOverloadedFunctionForReferenceBinding(Sema &S, 3157 Expr *Initializer, 3158 QualType &SourceType, 3159 QualType &UnqualifiedSourceType, 3160 QualType UnqualifiedTargetType, 3161 InitializationSequence &Sequence) { 3162 if (S.Context.getCanonicalType(UnqualifiedSourceType) == 3163 S.Context.OverloadTy) { 3164 DeclAccessPair Found; 3165 bool HadMultipleCandidates = false; 3166 if (FunctionDecl *Fn 3167 = S.ResolveAddressOfOverloadedFunction(Initializer, 3168 UnqualifiedTargetType, 3169 false, Found, 3170 &HadMultipleCandidates)) { 3171 Sequence.AddAddressOverloadResolutionStep(Fn, Found, 3172 HadMultipleCandidates); 3173 SourceType = Fn->getType(); 3174 UnqualifiedSourceType = SourceType.getUnqualifiedType(); 3175 } else if (!UnqualifiedTargetType->isRecordType()) { 3176 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 3177 return true; 3178 } 3179 } 3180 return false; 3181} 3182 3183static void TryReferenceInitializationCore(Sema &S, 3184 const InitializedEntity &Entity, 3185 const InitializationKind &Kind, 3186 Expr *Initializer, 3187 QualType cv1T1, QualType T1, 3188 Qualifiers T1Quals, 3189 QualType cv2T2, QualType T2, 3190 Qualifiers T2Quals, 3191 InitializationSequence &Sequence); 3192 3193static void TryValueInitialization(Sema &S, 3194 const InitializedEntity &Entity, 3195 const InitializationKind &Kind, 3196 InitializationSequence &Sequence, 3197 InitListExpr *InitList = 0); 3198 3199static void TryListInitialization(Sema &S, 3200 const InitializedEntity &Entity, 3201 const InitializationKind &Kind, 3202 InitListExpr *InitList, 3203 InitializationSequence &Sequence); 3204 3205/// \brief Attempt list initialization of a reference. 3206static void TryReferenceListInitialization(Sema &S, 3207 const InitializedEntity &Entity, 3208 const InitializationKind &Kind, 3209 InitListExpr *InitList, 3210 InitializationSequence &Sequence) { 3211 // First, catch C++03 where this isn't possible. 3212 if (!S.getLangOpts().CPlusPlus11) { 3213 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList); 3214 return; 3215 } 3216 3217 QualType DestType = Entity.getType(); 3218 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 3219 Qualifiers T1Quals; 3220 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); 3221 3222 // Reference initialization via an initializer list works thus: 3223 // If the initializer list consists of a single element that is 3224 // reference-related to the referenced type, bind directly to that element 3225 // (possibly creating temporaries). 3226 // Otherwise, initialize a temporary with the initializer list and 3227 // bind to that. 3228 if (InitList->getNumInits() == 1) { 3229 Expr *Initializer = InitList->getInit(0); 3230 QualType cv2T2 = Initializer->getType(); 3231 Qualifiers T2Quals; 3232 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); 3233 3234 // If this fails, creating a temporary wouldn't work either. 3235 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2, 3236 T1, Sequence)) 3237 return; 3238 3239 SourceLocation DeclLoc = Initializer->getLocStart(); 3240 bool dummy1, dummy2, dummy3; 3241 Sema::ReferenceCompareResult RefRelationship 3242 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, dummy1, 3243 dummy2, dummy3); 3244 if (RefRelationship >= Sema::Ref_Related) { 3245 // Try to bind the reference here. 3246 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1, 3247 T1Quals, cv2T2, T2, T2Quals, Sequence); 3248 if (Sequence) 3249 Sequence.RewrapReferenceInitList(cv1T1, InitList); 3250 return; 3251 } 3252 3253 // Update the initializer if we've resolved an overloaded function. 3254 if (Sequence.step_begin() != Sequence.step_end()) 3255 Sequence.RewrapReferenceInitList(cv1T1, InitList); 3256 } 3257 3258 // Not reference-related. Create a temporary and bind to that. 3259 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1); 3260 3261 TryListInitialization(S, TempEntity, Kind, InitList, Sequence); 3262 if (Sequence) { 3263 if (DestType->isRValueReferenceType() || 3264 (T1Quals.hasConst() && !T1Quals.hasVolatile())) 3265 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 3266 else 3267 Sequence.SetFailed( 3268 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); 3269 } 3270} 3271 3272/// \brief Attempt list initialization (C++0x [dcl.init.list]) 3273static void TryListInitialization(Sema &S, 3274 const InitializedEntity &Entity, 3275 const InitializationKind &Kind, 3276 InitListExpr *InitList, 3277 InitializationSequence &Sequence) { 3278 QualType DestType = Entity.getType(); 3279 3280 // C++ doesn't allow scalar initialization with more than one argument. 3281 // But C99 complex numbers are scalars and it makes sense there. 3282 if (S.getLangOpts().CPlusPlus && DestType->isScalarType() && 3283 !DestType->isAnyComplexType() && InitList->getNumInits() > 1) { 3284 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar); 3285 return; 3286 } 3287 if (DestType->isReferenceType()) { 3288 TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence); 3289 return; 3290 } 3291 if (DestType->isRecordType()) { 3292 if (S.RequireCompleteType(InitList->getLocStart(), DestType, 0)) { 3293 Sequence.setIncompleteTypeFailure(DestType); 3294 return; 3295 } 3296 3297 // C++11 [dcl.init.list]p3: 3298 // - If T is an aggregate, aggregate initialization is performed. 3299 if (!DestType->isAggregateType()) { 3300 if (S.getLangOpts().CPlusPlus11) { 3301 // - Otherwise, if the initializer list has no elements and T is a 3302 // class type with a default constructor, the object is 3303 // value-initialized. 3304 if (InitList->getNumInits() == 0) { 3305 CXXRecordDecl *RD = DestType->getAsCXXRecordDecl(); 3306 if (RD->hasDefaultConstructor()) { 3307 TryValueInitialization(S, Entity, Kind, Sequence, InitList); 3308 return; 3309 } 3310 } 3311 3312 // - Otherwise, if T is a specialization of std::initializer_list<E>, 3313 // an initializer_list object constructed [...] 3314 if (TryInitializerListConstruction(S, InitList, DestType, Sequence)) 3315 return; 3316 3317 // - Otherwise, if T is a class type, constructors are considered. 3318 Expr *InitListAsExpr = InitList; 3319 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType, 3320 Sequence, /*InitListSyntax*/true); 3321 } else 3322 Sequence.SetFailed( 3323 InitializationSequence::FK_InitListBadDestinationType); 3324 return; 3325 } 3326 } 3327 3328 InitListChecker CheckInitList(S, Entity, InitList, 3329 DestType, /*VerifyOnly=*/true); 3330 if (CheckInitList.HadError()) { 3331 Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed); 3332 return; 3333 } 3334 3335 // Add the list initialization step with the built init list. 3336 Sequence.AddListInitializationStep(DestType); 3337} 3338 3339/// \brief Try a reference initialization that involves calling a conversion 3340/// function. 3341static OverloadingResult TryRefInitWithConversionFunction(Sema &S, 3342 const InitializedEntity &Entity, 3343 const InitializationKind &Kind, 3344 Expr *Initializer, 3345 bool AllowRValues, 3346 InitializationSequence &Sequence) { 3347 QualType DestType = Entity.getType(); 3348 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 3349 QualType T1 = cv1T1.getUnqualifiedType(); 3350 QualType cv2T2 = Initializer->getType(); 3351 QualType T2 = cv2T2.getUnqualifiedType(); 3352 3353 bool DerivedToBase; 3354 bool ObjCConversion; 3355 bool ObjCLifetimeConversion; 3356 assert(!S.CompareReferenceRelationship(Initializer->getLocStart(), 3357 T1, T2, DerivedToBase, 3358 ObjCConversion, 3359 ObjCLifetimeConversion) && 3360 "Must have incompatible references when binding via conversion"); 3361 (void)DerivedToBase; 3362 (void)ObjCConversion; 3363 (void)ObjCLifetimeConversion; 3364 3365 // Build the candidate set directly in the initialization sequence 3366 // structure, so that it will persist if we fail. 3367 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 3368 CandidateSet.clear(); 3369 3370 // Determine whether we are allowed to call explicit constructors or 3371 // explicit conversion operators. 3372 bool AllowExplicit = Kind.AllowExplicit(); 3373 bool AllowExplicitConvs = Kind.allowExplicitConversionFunctions(); 3374 3375 const RecordType *T1RecordType = 0; 3376 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) && 3377 !S.RequireCompleteType(Kind.getLocation(), T1, 0)) { 3378 // The type we're converting to is a class type. Enumerate its constructors 3379 // to see if there is a suitable conversion. 3380 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl()); 3381 3382 DeclContext::lookup_result R = S.LookupConstructors(T1RecordDecl); 3383 // The container holding the constructors can under certain conditions 3384 // be changed while iterating (e.g. because of deserialization). 3385 // To be safe we copy the lookup results to a new container. 3386 SmallVector<NamedDecl*, 16> Ctors(R.begin(), R.end()); 3387 for (SmallVector<NamedDecl*, 16>::iterator 3388 CI = Ctors.begin(), CE = Ctors.end(); CI != CE; ++CI) { 3389 NamedDecl *D = *CI; 3390 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 3391 3392 // Find the constructor (which may be a template). 3393 CXXConstructorDecl *Constructor = 0; 3394 FunctionTemplateDecl *ConstructorTmpl = dyn_cast<FunctionTemplateDecl>(D); 3395 if (ConstructorTmpl) 3396 Constructor = cast<CXXConstructorDecl>( 3397 ConstructorTmpl->getTemplatedDecl()); 3398 else 3399 Constructor = cast<CXXConstructorDecl>(D); 3400 3401 if (!Constructor->isInvalidDecl() && 3402 Constructor->isConvertingConstructor(AllowExplicit)) { 3403 if (ConstructorTmpl) 3404 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 3405 /*ExplicitArgs*/ 0, 3406 Initializer, CandidateSet, 3407 /*SuppressUserConversions=*/true); 3408 else 3409 S.AddOverloadCandidate(Constructor, FoundDecl, 3410 Initializer, CandidateSet, 3411 /*SuppressUserConversions=*/true); 3412 } 3413 } 3414 } 3415 if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl()) 3416 return OR_No_Viable_Function; 3417 3418 const RecordType *T2RecordType = 0; 3419 if ((T2RecordType = T2->getAs<RecordType>()) && 3420 !S.RequireCompleteType(Kind.getLocation(), T2, 0)) { 3421 // The type we're converting from is a class type, enumerate its conversion 3422 // functions. 3423 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl()); 3424 3425 std::pair<CXXRecordDecl::conversion_iterator, 3426 CXXRecordDecl::conversion_iterator> 3427 Conversions = T2RecordDecl->getVisibleConversionFunctions(); 3428 for (CXXRecordDecl::conversion_iterator 3429 I = Conversions.first, E = Conversions.second; I != E; ++I) { 3430 NamedDecl *D = *I; 3431 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3432 if (isa<UsingShadowDecl>(D)) 3433 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3434 3435 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 3436 CXXConversionDecl *Conv; 3437 if (ConvTemplate) 3438 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3439 else 3440 Conv = cast<CXXConversionDecl>(D); 3441 3442 // If the conversion function doesn't return a reference type, 3443 // it can't be considered for this conversion unless we're allowed to 3444 // consider rvalues. 3445 // FIXME: Do we need to make sure that we only consider conversion 3446 // candidates with reference-compatible results? That might be needed to 3447 // break recursion. 3448 if ((AllowExplicitConvs || !Conv->isExplicit()) && 3449 (AllowRValues || Conv->getConversionType()->isLValueReferenceType())){ 3450 if (ConvTemplate) 3451 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 3452 ActingDC, Initializer, 3453 DestType, CandidateSet); 3454 else 3455 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 3456 Initializer, DestType, CandidateSet); 3457 } 3458 } 3459 } 3460 if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl()) 3461 return OR_No_Viable_Function; 3462 3463 SourceLocation DeclLoc = Initializer->getLocStart(); 3464 3465 // Perform overload resolution. If it fails, return the failed result. 3466 OverloadCandidateSet::iterator Best; 3467 if (OverloadingResult Result 3468 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) 3469 return Result; 3470 3471 FunctionDecl *Function = Best->Function; 3472 // This is the overload that will be used for this initialization step if we 3473 // use this initialization. Mark it as referenced. 3474 Function->setReferenced(); 3475 3476 // Compute the returned type of the conversion. 3477 if (isa<CXXConversionDecl>(Function)) 3478 T2 = Function->getResultType(); 3479 else 3480 T2 = cv1T1; 3481 3482 // Add the user-defined conversion step. 3483 bool HadMultipleCandidates = (CandidateSet.size() > 1); 3484 Sequence.AddUserConversionStep(Function, Best->FoundDecl, 3485 T2.getNonLValueExprType(S.Context), 3486 HadMultipleCandidates); 3487 3488 // Determine whether we need to perform derived-to-base or 3489 // cv-qualification adjustments. 3490 ExprValueKind VK = VK_RValue; 3491 if (T2->isLValueReferenceType()) 3492 VK = VK_LValue; 3493 else if (const RValueReferenceType *RRef = T2->getAs<RValueReferenceType>()) 3494 VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue; 3495 3496 bool NewDerivedToBase = false; 3497 bool NewObjCConversion = false; 3498 bool NewObjCLifetimeConversion = false; 3499 Sema::ReferenceCompareResult NewRefRelationship 3500 = S.CompareReferenceRelationship(DeclLoc, T1, 3501 T2.getNonLValueExprType(S.Context), 3502 NewDerivedToBase, NewObjCConversion, 3503 NewObjCLifetimeConversion); 3504 if (NewRefRelationship == Sema::Ref_Incompatible) { 3505 // If the type we've converted to is not reference-related to the 3506 // type we're looking for, then there is another conversion step 3507 // we need to perform to produce a temporary of the right type 3508 // that we'll be binding to. 3509 ImplicitConversionSequence ICS; 3510 ICS.setStandard(); 3511 ICS.Standard = Best->FinalConversion; 3512 T2 = ICS.Standard.getToType(2); 3513 Sequence.AddConversionSequenceStep(ICS, T2); 3514 } else if (NewDerivedToBase) 3515 Sequence.AddDerivedToBaseCastStep( 3516 S.Context.getQualifiedType(T1, 3517 T2.getNonReferenceType().getQualifiers()), 3518 VK); 3519 else if (NewObjCConversion) 3520 Sequence.AddObjCObjectConversionStep( 3521 S.Context.getQualifiedType(T1, 3522 T2.getNonReferenceType().getQualifiers())); 3523 3524 if (cv1T1.getQualifiers() != T2.getNonReferenceType().getQualifiers()) 3525 Sequence.AddQualificationConversionStep(cv1T1, VK); 3526 3527 Sequence.AddReferenceBindingStep(cv1T1, !T2->isReferenceType()); 3528 return OR_Success; 3529} 3530 3531static void CheckCXX98CompatAccessibleCopy(Sema &S, 3532 const InitializedEntity &Entity, 3533 Expr *CurInitExpr); 3534 3535/// \brief Attempt reference initialization (C++0x [dcl.init.ref]) 3536static void TryReferenceInitialization(Sema &S, 3537 const InitializedEntity &Entity, 3538 const InitializationKind &Kind, 3539 Expr *Initializer, 3540 InitializationSequence &Sequence) { 3541 QualType DestType = Entity.getType(); 3542 QualType cv1T1 = DestType->getAs<ReferenceType>()->getPointeeType(); 3543 Qualifiers T1Quals; 3544 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals); 3545 QualType cv2T2 = Initializer->getType(); 3546 Qualifiers T2Quals; 3547 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals); 3548 3549 // If the initializer is the address of an overloaded function, try 3550 // to resolve the overloaded function. If all goes well, T2 is the 3551 // type of the resulting function. 3552 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2, 3553 T1, Sequence)) 3554 return; 3555 3556 // Delegate everything else to a subfunction. 3557 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1, 3558 T1Quals, cv2T2, T2, T2Quals, Sequence); 3559} 3560 3561/// Converts the target of reference initialization so that it has the 3562/// appropriate qualifiers and value kind. 3563/// 3564/// In this case, 'x' is an 'int' lvalue, but it needs to be 'const int'. 3565/// \code 3566/// int x; 3567/// const int &r = x; 3568/// \endcode 3569/// 3570/// In this case the reference is binding to a bitfield lvalue, which isn't 3571/// valid. Perform a load to create a lifetime-extended temporary instead. 3572/// \code 3573/// const int &r = someStruct.bitfield; 3574/// \endcode 3575static ExprValueKind 3576convertQualifiersAndValueKindIfNecessary(Sema &S, 3577 InitializationSequence &Sequence, 3578 Expr *Initializer, 3579 QualType cv1T1, 3580 Qualifiers T1Quals, 3581 Qualifiers T2Quals, 3582 bool IsLValueRef) { 3583 bool IsNonAddressableType = Initializer->refersToBitField() || 3584 Initializer->refersToVectorElement(); 3585 3586 if (IsNonAddressableType) { 3587 // C++11 [dcl.init.ref]p5: [...] Otherwise, the reference shall be an 3588 // lvalue reference to a non-volatile const type, or the reference shall be 3589 // an rvalue reference. 3590 // 3591 // If not, we can't make a temporary and bind to that. Give up and allow the 3592 // error to be diagnosed later. 3593 if (IsLValueRef && (!T1Quals.hasConst() || T1Quals.hasVolatile())) { 3594 assert(Initializer->isGLValue()); 3595 return Initializer->getValueKind(); 3596 } 3597 3598 // Force a load so we can materialize a temporary. 3599 Sequence.AddLValueToRValueStep(cv1T1.getUnqualifiedType()); 3600 return VK_RValue; 3601 } 3602 3603 if (T1Quals != T2Quals) { 3604 Sequence.AddQualificationConversionStep(cv1T1, 3605 Initializer->getValueKind()); 3606 } 3607 3608 return Initializer->getValueKind(); 3609} 3610 3611 3612/// \brief Reference initialization without resolving overloaded functions. 3613static void TryReferenceInitializationCore(Sema &S, 3614 const InitializedEntity &Entity, 3615 const InitializationKind &Kind, 3616 Expr *Initializer, 3617 QualType cv1T1, QualType T1, 3618 Qualifiers T1Quals, 3619 QualType cv2T2, QualType T2, 3620 Qualifiers T2Quals, 3621 InitializationSequence &Sequence) { 3622 QualType DestType = Entity.getType(); 3623 SourceLocation DeclLoc = Initializer->getLocStart(); 3624 // Compute some basic properties of the types and the initializer. 3625 bool isLValueRef = DestType->isLValueReferenceType(); 3626 bool isRValueRef = !isLValueRef; 3627 bool DerivedToBase = false; 3628 bool ObjCConversion = false; 3629 bool ObjCLifetimeConversion = false; 3630 Expr::Classification InitCategory = Initializer->Classify(S.Context); 3631 Sema::ReferenceCompareResult RefRelationship 3632 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, DerivedToBase, 3633 ObjCConversion, ObjCLifetimeConversion); 3634 3635 // C++0x [dcl.init.ref]p5: 3636 // A reference to type "cv1 T1" is initialized by an expression of type 3637 // "cv2 T2" as follows: 3638 // 3639 // - If the reference is an lvalue reference and the initializer 3640 // expression 3641 // Note the analogous bullet points for rvlaue refs to functions. Because 3642 // there are no function rvalues in C++, rvalue refs to functions are treated 3643 // like lvalue refs. 3644 OverloadingResult ConvOvlResult = OR_Success; 3645 bool T1Function = T1->isFunctionType(); 3646 if (isLValueRef || T1Function) { 3647 if (InitCategory.isLValue() && 3648 (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification || 3649 (Kind.isCStyleOrFunctionalCast() && 3650 RefRelationship == Sema::Ref_Related))) { 3651 // - is an lvalue (but is not a bit-field), and "cv1 T1" is 3652 // reference-compatible with "cv2 T2," or 3653 // 3654 // Per C++ [over.best.ics]p2, we don't diagnose whether the lvalue is a 3655 // bit-field when we're determining whether the reference initialization 3656 // can occur. However, we do pay attention to whether it is a bit-field 3657 // to decide whether we're actually binding to a temporary created from 3658 // the bit-field. 3659 if (DerivedToBase) 3660 Sequence.AddDerivedToBaseCastStep( 3661 S.Context.getQualifiedType(T1, T2Quals), 3662 VK_LValue); 3663 else if (ObjCConversion) 3664 Sequence.AddObjCObjectConversionStep( 3665 S.Context.getQualifiedType(T1, T2Quals)); 3666 3667 ExprValueKind ValueKind = 3668 convertQualifiersAndValueKindIfNecessary(S, Sequence, Initializer, 3669 cv1T1, T1Quals, T2Quals, 3670 isLValueRef); 3671 Sequence.AddReferenceBindingStep(cv1T1, ValueKind == VK_RValue); 3672 return; 3673 } 3674 3675 // - has a class type (i.e., T2 is a class type), where T1 is not 3676 // reference-related to T2, and can be implicitly converted to an 3677 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible 3678 // with "cv3 T3" (this conversion is selected by enumerating the 3679 // applicable conversion functions (13.3.1.6) and choosing the best 3680 // one through overload resolution (13.3)), 3681 // If we have an rvalue ref to function type here, the rhs must be 3682 // an rvalue. 3683 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() && 3684 (isLValueRef || InitCategory.isRValue())) { 3685 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, Kind, 3686 Initializer, 3687 /*AllowRValues=*/isRValueRef, 3688 Sequence); 3689 if (ConvOvlResult == OR_Success) 3690 return; 3691 if (ConvOvlResult != OR_No_Viable_Function) { 3692 Sequence.SetOverloadFailure( 3693 InitializationSequence::FK_ReferenceInitOverloadFailed, 3694 ConvOvlResult); 3695 } 3696 } 3697 } 3698 3699 // - Otherwise, the reference shall be an lvalue reference to a 3700 // non-volatile const type (i.e., cv1 shall be const), or the reference 3701 // shall be an rvalue reference. 3702 if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile())) { 3703 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) 3704 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 3705 else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 3706 Sequence.SetOverloadFailure( 3707 InitializationSequence::FK_ReferenceInitOverloadFailed, 3708 ConvOvlResult); 3709 else 3710 Sequence.SetFailed(InitCategory.isLValue() 3711 ? (RefRelationship == Sema::Ref_Related 3712 ? InitializationSequence::FK_ReferenceInitDropsQualifiers 3713 : InitializationSequence::FK_NonConstLValueReferenceBindingToUnrelated) 3714 : InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary); 3715 3716 return; 3717 } 3718 3719 // - If the initializer expression 3720 // - is an xvalue, class prvalue, array prvalue, or function lvalue and 3721 // "cv1 T1" is reference-compatible with "cv2 T2" 3722 // Note: functions are handled below. 3723 if (!T1Function && 3724 (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification || 3725 (Kind.isCStyleOrFunctionalCast() && 3726 RefRelationship == Sema::Ref_Related)) && 3727 (InitCategory.isXValue() || 3728 (InitCategory.isPRValue() && T2->isRecordType()) || 3729 (InitCategory.isPRValue() && T2->isArrayType()))) { 3730 ExprValueKind ValueKind = InitCategory.isXValue()? VK_XValue : VK_RValue; 3731 if (InitCategory.isPRValue() && T2->isRecordType()) { 3732 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the 3733 // compiler the freedom to perform a copy here or bind to the 3734 // object, while C++0x requires that we bind directly to the 3735 // object. Hence, we always bind to the object without making an 3736 // extra copy. However, in C++03 requires that we check for the 3737 // presence of a suitable copy constructor: 3738 // 3739 // The constructor that would be used to make the copy shall 3740 // be callable whether or not the copy is actually done. 3741 if (!S.getLangOpts().CPlusPlus11 && !S.getLangOpts().MicrosoftExt) 3742 Sequence.AddExtraneousCopyToTemporary(cv2T2); 3743 else if (S.getLangOpts().CPlusPlus11) 3744 CheckCXX98CompatAccessibleCopy(S, Entity, Initializer); 3745 } 3746 3747 if (DerivedToBase) 3748 Sequence.AddDerivedToBaseCastStep(S.Context.getQualifiedType(T1, T2Quals), 3749 ValueKind); 3750 else if (ObjCConversion) 3751 Sequence.AddObjCObjectConversionStep( 3752 S.Context.getQualifiedType(T1, T2Quals)); 3753 3754 ValueKind = convertQualifiersAndValueKindIfNecessary(S, Sequence, 3755 Initializer, cv1T1, 3756 T1Quals, T2Quals, 3757 isLValueRef); 3758 3759 Sequence.AddReferenceBindingStep(cv1T1, ValueKind == VK_RValue); 3760 return; 3761 } 3762 3763 // - has a class type (i.e., T2 is a class type), where T1 is not 3764 // reference-related to T2, and can be implicitly converted to an 3765 // xvalue, class prvalue, or function lvalue of type "cv3 T3", 3766 // where "cv1 T1" is reference-compatible with "cv3 T3", 3767 if (T2->isRecordType()) { 3768 if (RefRelationship == Sema::Ref_Incompatible) { 3769 ConvOvlResult = TryRefInitWithConversionFunction(S, Entity, 3770 Kind, Initializer, 3771 /*AllowRValues=*/true, 3772 Sequence); 3773 if (ConvOvlResult) 3774 Sequence.SetOverloadFailure( 3775 InitializationSequence::FK_ReferenceInitOverloadFailed, 3776 ConvOvlResult); 3777 3778 return; 3779 } 3780 3781 if ((RefRelationship == Sema::Ref_Compatible || 3782 RefRelationship == Sema::Ref_Compatible_With_Added_Qualification) && 3783 isRValueRef && InitCategory.isLValue()) { 3784 Sequence.SetFailed( 3785 InitializationSequence::FK_RValueReferenceBindingToLValue); 3786 return; 3787 } 3788 3789 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 3790 return; 3791 } 3792 3793 // - Otherwise, a temporary of type "cv1 T1" is created and initialized 3794 // from the initializer expression using the rules for a non-reference 3795 // copy initialization (8.5). The reference is then bound to the 3796 // temporary. [...] 3797 3798 // Determine whether we are allowed to call explicit constructors or 3799 // explicit conversion operators. 3800 bool AllowExplicit = Kind.AllowExplicit(); 3801 3802 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(cv1T1); 3803 3804 ImplicitConversionSequence ICS 3805 = S.TryImplicitConversion(Initializer, TempEntity.getType(), 3806 /*SuppressUserConversions*/ false, 3807 AllowExplicit, 3808 /*FIXME:InOverloadResolution=*/false, 3809 /*CStyle=*/Kind.isCStyleOrFunctionalCast(), 3810 /*AllowObjCWritebackConversion=*/false); 3811 3812 if (ICS.isBad()) { 3813 // FIXME: Use the conversion function set stored in ICS to turn 3814 // this into an overloading ambiguity diagnostic. However, we need 3815 // to keep that set as an OverloadCandidateSet rather than as some 3816 // other kind of set. 3817 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty()) 3818 Sequence.SetOverloadFailure( 3819 InitializationSequence::FK_ReferenceInitOverloadFailed, 3820 ConvOvlResult); 3821 else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) 3822 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 3823 else 3824 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed); 3825 return; 3826 } else { 3827 Sequence.AddConversionSequenceStep(ICS, TempEntity.getType()); 3828 } 3829 3830 // [...] If T1 is reference-related to T2, cv1 must be the 3831 // same cv-qualification as, or greater cv-qualification 3832 // than, cv2; otherwise, the program is ill-formed. 3833 unsigned T1CVRQuals = T1Quals.getCVRQualifiers(); 3834 unsigned T2CVRQuals = T2Quals.getCVRQualifiers(); 3835 if (RefRelationship == Sema::Ref_Related && 3836 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) { 3837 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers); 3838 return; 3839 } 3840 3841 // [...] If T1 is reference-related to T2 and the reference is an rvalue 3842 // reference, the initializer expression shall not be an lvalue. 3843 if (RefRelationship >= Sema::Ref_Related && !isLValueRef && 3844 InitCategory.isLValue()) { 3845 Sequence.SetFailed( 3846 InitializationSequence::FK_RValueReferenceBindingToLValue); 3847 return; 3848 } 3849 3850 Sequence.AddReferenceBindingStep(cv1T1, /*bindingTemporary=*/true); 3851 return; 3852} 3853 3854/// \brief Attempt character array initialization from a string literal 3855/// (C++ [dcl.init.string], C99 6.7.8). 3856static void TryStringLiteralInitialization(Sema &S, 3857 const InitializedEntity &Entity, 3858 const InitializationKind &Kind, 3859 Expr *Initializer, 3860 InitializationSequence &Sequence) { 3861 Sequence.AddStringInitStep(Entity.getType()); 3862} 3863 3864/// \brief Attempt value initialization (C++ [dcl.init]p7). 3865static void TryValueInitialization(Sema &S, 3866 const InitializedEntity &Entity, 3867 const InitializationKind &Kind, 3868 InitializationSequence &Sequence, 3869 InitListExpr *InitList) { 3870 assert((!InitList || InitList->getNumInits() == 0) && 3871 "Shouldn't use value-init for non-empty init lists"); 3872 3873 // C++98 [dcl.init]p5, C++11 [dcl.init]p7: 3874 // 3875 // To value-initialize an object of type T means: 3876 QualType T = Entity.getType(); 3877 3878 // -- if T is an array type, then each element is value-initialized; 3879 T = S.Context.getBaseElementType(T); 3880 3881 if (const RecordType *RT = T->getAs<RecordType>()) { 3882 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 3883 bool NeedZeroInitialization = true; 3884 if (!S.getLangOpts().CPlusPlus11) { 3885 // C++98: 3886 // -- if T is a class type (clause 9) with a user-declared constructor 3887 // (12.1), then the default constructor for T is called (and the 3888 // initialization is ill-formed if T has no accessible default 3889 // constructor); 3890 if (ClassDecl->hasUserDeclaredConstructor()) 3891 NeedZeroInitialization = false; 3892 } else { 3893 // C++11: 3894 // -- if T is a class type (clause 9) with either no default constructor 3895 // (12.1 [class.ctor]) or a default constructor that is user-provided 3896 // or deleted, then the object is default-initialized; 3897 CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl); 3898 if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted()) 3899 NeedZeroInitialization = false; 3900 } 3901 3902 // -- if T is a (possibly cv-qualified) non-union class type without a 3903 // user-provided or deleted default constructor, then the object is 3904 // zero-initialized and, if T has a non-trivial default constructor, 3905 // default-initialized; 3906 // The 'non-union' here was removed by DR1502. The 'non-trivial default 3907 // constructor' part was removed by DR1507. 3908 if (NeedZeroInitialization) 3909 Sequence.AddZeroInitializationStep(Entity.getType()); 3910 3911 // C++03: 3912 // -- if T is a non-union class type without a user-declared constructor, 3913 // then every non-static data member and base class component of T is 3914 // value-initialized; 3915 // [...] A program that calls for [...] value-initialization of an 3916 // entity of reference type is ill-formed. 3917 // 3918 // C++11 doesn't need this handling, because value-initialization does not 3919 // occur recursively there, and the implicit default constructor is 3920 // defined as deleted in the problematic cases. 3921 if (!S.getLangOpts().CPlusPlus11 && 3922 ClassDecl->hasUninitializedReferenceMember()) { 3923 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForReference); 3924 return; 3925 } 3926 3927 // If this is list-value-initialization, pass the empty init list on when 3928 // building the constructor call. This affects the semantics of a few 3929 // things (such as whether an explicit default constructor can be called). 3930 Expr *InitListAsExpr = InitList; 3931 MultiExprArg Args(&InitListAsExpr, InitList ? 1 : 0); 3932 bool InitListSyntax = InitList; 3933 3934 return TryConstructorInitialization(S, Entity, Kind, Args, T, Sequence, 3935 InitListSyntax); 3936 } 3937 } 3938 3939 Sequence.AddZeroInitializationStep(Entity.getType()); 3940} 3941 3942/// \brief Attempt default initialization (C++ [dcl.init]p6). 3943static void TryDefaultInitialization(Sema &S, 3944 const InitializedEntity &Entity, 3945 const InitializationKind &Kind, 3946 InitializationSequence &Sequence) { 3947 assert(Kind.getKind() == InitializationKind::IK_Default); 3948 3949 // C++ [dcl.init]p6: 3950 // To default-initialize an object of type T means: 3951 // - if T is an array type, each element is default-initialized; 3952 QualType DestType = S.Context.getBaseElementType(Entity.getType()); 3953 3954 // - if T is a (possibly cv-qualified) class type (Clause 9), the default 3955 // constructor for T is called (and the initialization is ill-formed if 3956 // T has no accessible default constructor); 3957 if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) { 3958 TryConstructorInitialization(S, Entity, Kind, None, DestType, Sequence); 3959 return; 3960 } 3961 3962 // - otherwise, no initialization is performed. 3963 3964 // If a program calls for the default initialization of an object of 3965 // a const-qualified type T, T shall be a class type with a user-provided 3966 // default constructor. 3967 if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) { 3968 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst); 3969 return; 3970 } 3971 3972 // If the destination type has a lifetime property, zero-initialize it. 3973 if (DestType.getQualifiers().hasObjCLifetime()) { 3974 Sequence.AddZeroInitializationStep(Entity.getType()); 3975 return; 3976 } 3977} 3978 3979/// \brief Attempt a user-defined conversion between two types (C++ [dcl.init]), 3980/// which enumerates all conversion functions and performs overload resolution 3981/// to select the best. 3982static void TryUserDefinedConversion(Sema &S, 3983 const InitializedEntity &Entity, 3984 const InitializationKind &Kind, 3985 Expr *Initializer, 3986 InitializationSequence &Sequence) { 3987 QualType DestType = Entity.getType(); 3988 assert(!DestType->isReferenceType() && "References are handled elsewhere"); 3989 QualType SourceType = Initializer->getType(); 3990 assert((DestType->isRecordType() || SourceType->isRecordType()) && 3991 "Must have a class type to perform a user-defined conversion"); 3992 3993 // Build the candidate set directly in the initialization sequence 3994 // structure, so that it will persist if we fail. 3995 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet(); 3996 CandidateSet.clear(); 3997 3998 // Determine whether we are allowed to call explicit constructors or 3999 // explicit conversion operators. 4000 bool AllowExplicit = Kind.AllowExplicit(); 4001 4002 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) { 4003 // The type we're converting to is a class type. Enumerate its constructors 4004 // to see if there is a suitable conversion. 4005 CXXRecordDecl *DestRecordDecl 4006 = cast<CXXRecordDecl>(DestRecordType->getDecl()); 4007 4008 // Try to complete the type we're converting to. 4009 if (!S.RequireCompleteType(Kind.getLocation(), DestType, 0)) { 4010 DeclContext::lookup_result R = S.LookupConstructors(DestRecordDecl); 4011 // The container holding the constructors can under certain conditions 4012 // be changed while iterating. To be safe we copy the lookup results 4013 // to a new container. 4014 SmallVector<NamedDecl*, 8> CopyOfCon(R.begin(), R.end()); 4015 for (SmallVector<NamedDecl*, 8>::iterator 4016 Con = CopyOfCon.begin(), ConEnd = CopyOfCon.end(); 4017 Con != ConEnd; ++Con) { 4018 NamedDecl *D = *Con; 4019 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 4020 4021 // Find the constructor (which may be a template). 4022 CXXConstructorDecl *Constructor = 0; 4023 FunctionTemplateDecl *ConstructorTmpl 4024 = dyn_cast<FunctionTemplateDecl>(D); 4025 if (ConstructorTmpl) 4026 Constructor = cast<CXXConstructorDecl>( 4027 ConstructorTmpl->getTemplatedDecl()); 4028 else 4029 Constructor = cast<CXXConstructorDecl>(D); 4030 4031 if (!Constructor->isInvalidDecl() && 4032 Constructor->isConvertingConstructor(AllowExplicit)) { 4033 if (ConstructorTmpl) 4034 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 4035 /*ExplicitArgs*/ 0, 4036 Initializer, CandidateSet, 4037 /*SuppressUserConversions=*/true); 4038 else 4039 S.AddOverloadCandidate(Constructor, FoundDecl, 4040 Initializer, CandidateSet, 4041 /*SuppressUserConversions=*/true); 4042 } 4043 } 4044 } 4045 } 4046 4047 SourceLocation DeclLoc = Initializer->getLocStart(); 4048 4049 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) { 4050 // The type we're converting from is a class type, enumerate its conversion 4051 // functions. 4052 4053 // We can only enumerate the conversion functions for a complete type; if 4054 // the type isn't complete, simply skip this step. 4055 if (!S.RequireCompleteType(DeclLoc, SourceType, 0)) { 4056 CXXRecordDecl *SourceRecordDecl 4057 = cast<CXXRecordDecl>(SourceRecordType->getDecl()); 4058 4059 std::pair<CXXRecordDecl::conversion_iterator, 4060 CXXRecordDecl::conversion_iterator> 4061 Conversions = SourceRecordDecl->getVisibleConversionFunctions(); 4062 for (CXXRecordDecl::conversion_iterator 4063 I = Conversions.first, E = Conversions.second; I != E; ++I) { 4064 NamedDecl *D = *I; 4065 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 4066 if (isa<UsingShadowDecl>(D)) 4067 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 4068 4069 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D); 4070 CXXConversionDecl *Conv; 4071 if (ConvTemplate) 4072 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 4073 else 4074 Conv = cast<CXXConversionDecl>(D); 4075 4076 if (AllowExplicit || !Conv->isExplicit()) { 4077 if (ConvTemplate) 4078 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), 4079 ActingDC, Initializer, DestType, 4080 CandidateSet); 4081 else 4082 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, 4083 Initializer, DestType, CandidateSet); 4084 } 4085 } 4086 } 4087 } 4088 4089 // Perform overload resolution. If it fails, return the failed result. 4090 OverloadCandidateSet::iterator Best; 4091 if (OverloadingResult Result 4092 = CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 4093 Sequence.SetOverloadFailure( 4094 InitializationSequence::FK_UserConversionOverloadFailed, 4095 Result); 4096 return; 4097 } 4098 4099 FunctionDecl *Function = Best->Function; 4100 Function->setReferenced(); 4101 bool HadMultipleCandidates = (CandidateSet.size() > 1); 4102 4103 if (isa<CXXConstructorDecl>(Function)) { 4104 // Add the user-defined conversion step. Any cv-qualification conversion is 4105 // subsumed by the initialization. Per DR5, the created temporary is of the 4106 // cv-unqualified type of the destination. 4107 Sequence.AddUserConversionStep(Function, Best->FoundDecl, 4108 DestType.getUnqualifiedType(), 4109 HadMultipleCandidates); 4110 return; 4111 } 4112 4113 // Add the user-defined conversion step that calls the conversion function. 4114 QualType ConvType = Function->getCallResultType(); 4115 if (ConvType->getAs<RecordType>()) { 4116 // If we're converting to a class type, there may be an copy of 4117 // the resulting temporary object (possible to create an object of 4118 // a base class type). That copy is not a separate conversion, so 4119 // we just make a note of the actual destination type (possibly a 4120 // base class of the type returned by the conversion function) and 4121 // let the user-defined conversion step handle the conversion. 4122 Sequence.AddUserConversionStep(Function, Best->FoundDecl, DestType, 4123 HadMultipleCandidates); 4124 return; 4125 } 4126 4127 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType, 4128 HadMultipleCandidates); 4129 4130 // If the conversion following the call to the conversion function 4131 // is interesting, add it as a separate step. 4132 if (Best->FinalConversion.First || Best->FinalConversion.Second || 4133 Best->FinalConversion.Third) { 4134 ImplicitConversionSequence ICS; 4135 ICS.setStandard(); 4136 ICS.Standard = Best->FinalConversion; 4137 Sequence.AddConversionSequenceStep(ICS, DestType); 4138 } 4139} 4140 4141/// The non-zero enum values here are indexes into diagnostic alternatives. 4142enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar }; 4143 4144/// Determines whether this expression is an acceptable ICR source. 4145static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e, 4146 bool isAddressOf, bool &isWeakAccess) { 4147 // Skip parens. 4148 e = e->IgnoreParens(); 4149 4150 // Skip address-of nodes. 4151 if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) { 4152 if (op->getOpcode() == UO_AddrOf) 4153 return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true, 4154 isWeakAccess); 4155 4156 // Skip certain casts. 4157 } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) { 4158 switch (ce->getCastKind()) { 4159 case CK_Dependent: 4160 case CK_BitCast: 4161 case CK_LValueBitCast: 4162 case CK_NoOp: 4163 return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf, isWeakAccess); 4164 4165 case CK_ArrayToPointerDecay: 4166 return IIK_nonscalar; 4167 4168 case CK_NullToPointer: 4169 return IIK_okay; 4170 4171 default: 4172 break; 4173 } 4174 4175 // If we have a declaration reference, it had better be a local variable. 4176 } else if (isa<DeclRefExpr>(e)) { 4177 // set isWeakAccess to true, to mean that there will be an implicit 4178 // load which requires a cleanup. 4179 if (e->getType().getObjCLifetime() == Qualifiers::OCL_Weak) 4180 isWeakAccess = true; 4181 4182 if (!isAddressOf) return IIK_nonlocal; 4183 4184 VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl()); 4185 if (!var) return IIK_nonlocal; 4186 4187 return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal); 4188 4189 // If we have a conditional operator, check both sides. 4190 } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) { 4191 if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf, 4192 isWeakAccess)) 4193 return iik; 4194 4195 return isInvalidICRSource(C, cond->getRHS(), isAddressOf, isWeakAccess); 4196 4197 // These are never scalar. 4198 } else if (isa<ArraySubscriptExpr>(e)) { 4199 return IIK_nonscalar; 4200 4201 // Otherwise, it needs to be a null pointer constant. 4202 } else { 4203 return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull) 4204 ? IIK_okay : IIK_nonlocal); 4205 } 4206 4207 return IIK_nonlocal; 4208} 4209 4210/// Check whether the given expression is a valid operand for an 4211/// indirect copy/restore. 4212static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) { 4213 assert(src->isRValue()); 4214 bool isWeakAccess = false; 4215 InvalidICRKind iik = isInvalidICRSource(S.Context, src, false, isWeakAccess); 4216 // If isWeakAccess to true, there will be an implicit 4217 // load which requires a cleanup. 4218 if (S.getLangOpts().ObjCAutoRefCount && isWeakAccess) 4219 S.ExprNeedsCleanups = true; 4220 4221 if (iik == IIK_okay) return; 4222 4223 S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback) 4224 << ((unsigned) iik - 1) // shift index into diagnostic explanations 4225 << src->getSourceRange(); 4226} 4227 4228/// \brief Determine whether we have compatible array types for the 4229/// purposes of GNU by-copy array initialization. 4230static bool hasCompatibleArrayTypes(ASTContext &Context, 4231 const ArrayType *Dest, 4232 const ArrayType *Source) { 4233 // If the source and destination array types are equivalent, we're 4234 // done. 4235 if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0))) 4236 return true; 4237 4238 // Make sure that the element types are the same. 4239 if (!Context.hasSameType(Dest->getElementType(), Source->getElementType())) 4240 return false; 4241 4242 // The only mismatch we allow is when the destination is an 4243 // incomplete array type and the source is a constant array type. 4244 return Source->isConstantArrayType() && Dest->isIncompleteArrayType(); 4245} 4246 4247static bool tryObjCWritebackConversion(Sema &S, 4248 InitializationSequence &Sequence, 4249 const InitializedEntity &Entity, 4250 Expr *Initializer) { 4251 bool ArrayDecay = false; 4252 QualType ArgType = Initializer->getType(); 4253 QualType ArgPointee; 4254 if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) { 4255 ArrayDecay = true; 4256 ArgPointee = ArgArrayType->getElementType(); 4257 ArgType = S.Context.getPointerType(ArgPointee); 4258 } 4259 4260 // Handle write-back conversion. 4261 QualType ConvertedArgType; 4262 if (!S.isObjCWritebackConversion(ArgType, Entity.getType(), 4263 ConvertedArgType)) 4264 return false; 4265 4266 // We should copy unless we're passing to an argument explicitly 4267 // marked 'out'. 4268 bool ShouldCopy = true; 4269 if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl())) 4270 ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out); 4271 4272 // Do we need an lvalue conversion? 4273 if (ArrayDecay || Initializer->isGLValue()) { 4274 ImplicitConversionSequence ICS; 4275 ICS.setStandard(); 4276 ICS.Standard.setAsIdentityConversion(); 4277 4278 QualType ResultType; 4279 if (ArrayDecay) { 4280 ICS.Standard.First = ICK_Array_To_Pointer; 4281 ResultType = S.Context.getPointerType(ArgPointee); 4282 } else { 4283 ICS.Standard.First = ICK_Lvalue_To_Rvalue; 4284 ResultType = Initializer->getType().getNonLValueExprType(S.Context); 4285 } 4286 4287 Sequence.AddConversionSequenceStep(ICS, ResultType); 4288 } 4289 4290 Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy); 4291 return true; 4292} 4293 4294static bool TryOCLSamplerInitialization(Sema &S, 4295 InitializationSequence &Sequence, 4296 QualType DestType, 4297 Expr *Initializer) { 4298 if (!S.getLangOpts().OpenCL || !DestType->isSamplerT() || 4299 !Initializer->isIntegerConstantExpr(S.getASTContext())) 4300 return false; 4301 4302 Sequence.AddOCLSamplerInitStep(DestType); 4303 return true; 4304} 4305 4306// 4307// OpenCL 1.2 spec, s6.12.10 4308// 4309// The event argument can also be used to associate the 4310// async_work_group_copy with a previous async copy allowing 4311// an event to be shared by multiple async copies; otherwise 4312// event should be zero. 4313// 4314static bool TryOCLZeroEventInitialization(Sema &S, 4315 InitializationSequence &Sequence, 4316 QualType DestType, 4317 Expr *Initializer) { 4318 if (!S.getLangOpts().OpenCL || !DestType->isEventT() || 4319 !Initializer->isIntegerConstantExpr(S.getASTContext()) || 4320 (Initializer->EvaluateKnownConstInt(S.getASTContext()) != 0)) 4321 return false; 4322 4323 Sequence.AddOCLZeroEventStep(DestType); 4324 return true; 4325} 4326 4327InitializationSequence::InitializationSequence(Sema &S, 4328 const InitializedEntity &Entity, 4329 const InitializationKind &Kind, 4330 MultiExprArg Args) 4331 : FailedCandidateSet(Kind.getLocation()) { 4332 ASTContext &Context = S.Context; 4333 4334 // Eliminate non-overload placeholder types in the arguments. We 4335 // need to do this before checking whether types are dependent 4336 // because lowering a pseudo-object expression might well give us 4337 // something of dependent type. 4338 for (unsigned I = 0, E = Args.size(); I != E; ++I) 4339 if (Args[I]->getType()->isNonOverloadPlaceholderType()) { 4340 // FIXME: should we be doing this here? 4341 ExprResult result = S.CheckPlaceholderExpr(Args[I]); 4342 if (result.isInvalid()) { 4343 SetFailed(FK_PlaceholderType); 4344 return; 4345 } 4346 Args[I] = result.take(); 4347 } 4348 4349 // C++0x [dcl.init]p16: 4350 // The semantics of initializers are as follows. The destination type is 4351 // the type of the object or reference being initialized and the source 4352 // type is the type of the initializer expression. The source type is not 4353 // defined when the initializer is a braced-init-list or when it is a 4354 // parenthesized list of expressions. 4355 QualType DestType = Entity.getType(); 4356 4357 if (DestType->isDependentType() || 4358 Expr::hasAnyTypeDependentArguments(Args)) { 4359 SequenceKind = DependentSequence; 4360 return; 4361 } 4362 4363 // Almost everything is a normal sequence. 4364 setSequenceKind(NormalSequence); 4365 4366 QualType SourceType; 4367 Expr *Initializer = 0; 4368 if (Args.size() == 1) { 4369 Initializer = Args[0]; 4370 if (!isa<InitListExpr>(Initializer)) 4371 SourceType = Initializer->getType(); 4372 } 4373 4374 // - If the initializer is a (non-parenthesized) braced-init-list, the 4375 // object is list-initialized (8.5.4). 4376 if (Kind.getKind() != InitializationKind::IK_Direct) { 4377 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) { 4378 TryListInitialization(S, Entity, Kind, InitList, *this); 4379 return; 4380 } 4381 } 4382 4383 // - If the destination type is a reference type, see 8.5.3. 4384 if (DestType->isReferenceType()) { 4385 // C++0x [dcl.init.ref]p1: 4386 // A variable declared to be a T& or T&&, that is, "reference to type T" 4387 // (8.3.2), shall be initialized by an object, or function, of type T or 4388 // by an object that can be converted into a T. 4389 // (Therefore, multiple arguments are not permitted.) 4390 if (Args.size() != 1) 4391 SetFailed(FK_TooManyInitsForReference); 4392 else 4393 TryReferenceInitialization(S, Entity, Kind, Args[0], *this); 4394 return; 4395 } 4396 4397 // - If the initializer is (), the object is value-initialized. 4398 if (Kind.getKind() == InitializationKind::IK_Value || 4399 (Kind.getKind() == InitializationKind::IK_Direct && Args.empty())) { 4400 TryValueInitialization(S, Entity, Kind, *this); 4401 return; 4402 } 4403 4404 // Handle default initialization. 4405 if (Kind.getKind() == InitializationKind::IK_Default) { 4406 TryDefaultInitialization(S, Entity, Kind, *this); 4407 return; 4408 } 4409 4410 // - If the destination type is an array of characters, an array of 4411 // char16_t, an array of char32_t, or an array of wchar_t, and the 4412 // initializer is a string literal, see 8.5.2. 4413 // - Otherwise, if the destination type is an array, the program is 4414 // ill-formed. 4415 if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) { 4416 if (Initializer && isa<VariableArrayType>(DestAT)) { 4417 SetFailed(FK_VariableLengthArrayHasInitializer); 4418 return; 4419 } 4420 4421 if (Initializer) { 4422 switch (IsStringInit(Initializer, DestAT, Context)) { 4423 case SIF_None: 4424 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this); 4425 return; 4426 case SIF_NarrowStringIntoWideChar: 4427 SetFailed(FK_NarrowStringIntoWideCharArray); 4428 return; 4429 case SIF_WideStringIntoChar: 4430 SetFailed(FK_WideStringIntoCharArray); 4431 return; 4432 case SIF_IncompatWideStringIntoWideChar: 4433 SetFailed(FK_IncompatWideStringIntoWideChar); 4434 return; 4435 case SIF_Other: 4436 break; 4437 } 4438 } 4439 4440 // Note: as an GNU C extension, we allow initialization of an 4441 // array from a compound literal that creates an array of the same 4442 // type, so long as the initializer has no side effects. 4443 if (!S.getLangOpts().CPlusPlus && Initializer && 4444 isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) && 4445 Initializer->getType()->isArrayType()) { 4446 const ArrayType *SourceAT 4447 = Context.getAsArrayType(Initializer->getType()); 4448 if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT)) 4449 SetFailed(FK_ArrayTypeMismatch); 4450 else if (Initializer->HasSideEffects(S.Context)) 4451 SetFailed(FK_NonConstantArrayInit); 4452 else { 4453 AddArrayInitStep(DestType); 4454 } 4455 } 4456 // Note: as a GNU C++ extension, we allow list-initialization of a 4457 // class member of array type from a parenthesized initializer list. 4458 else if (S.getLangOpts().CPlusPlus && 4459 Entity.getKind() == InitializedEntity::EK_Member && 4460 Initializer && isa<InitListExpr>(Initializer)) { 4461 TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer), 4462 *this); 4463 AddParenthesizedArrayInitStep(DestType); 4464 } else if (DestAT->getElementType()->isCharType()) 4465 SetFailed(FK_ArrayNeedsInitListOrStringLiteral); 4466 else if (IsWideCharCompatible(DestAT->getElementType(), Context)) 4467 SetFailed(FK_ArrayNeedsInitListOrWideStringLiteral); 4468 else 4469 SetFailed(FK_ArrayNeedsInitList); 4470 4471 return; 4472 } 4473 4474 // Determine whether we should consider writeback conversions for 4475 // Objective-C ARC. 4476 bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount && 4477 Entity.getKind() == InitializedEntity::EK_Parameter; 4478 4479 // We're at the end of the line for C: it's either a write-back conversion 4480 // or it's a C assignment. There's no need to check anything else. 4481 if (!S.getLangOpts().CPlusPlus) { 4482 // If allowed, check whether this is an Objective-C writeback conversion. 4483 if (allowObjCWritebackConversion && 4484 tryObjCWritebackConversion(S, *this, Entity, Initializer)) { 4485 return; 4486 } 4487 4488 if (TryOCLSamplerInitialization(S, *this, DestType, Initializer)) 4489 return; 4490 4491 if (TryOCLZeroEventInitialization(S, *this, DestType, Initializer)) 4492 return; 4493 4494 // Handle initialization in C 4495 AddCAssignmentStep(DestType); 4496 MaybeProduceObjCObject(S, *this, Entity); 4497 return; 4498 } 4499 4500 assert(S.getLangOpts().CPlusPlus); 4501 4502 // - If the destination type is a (possibly cv-qualified) class type: 4503 if (DestType->isRecordType()) { 4504 // - If the initialization is direct-initialization, or if it is 4505 // copy-initialization where the cv-unqualified version of the 4506 // source type is the same class as, or a derived class of, the 4507 // class of the destination, constructors are considered. [...] 4508 if (Kind.getKind() == InitializationKind::IK_Direct || 4509 (Kind.getKind() == InitializationKind::IK_Copy && 4510 (Context.hasSameUnqualifiedType(SourceType, DestType) || 4511 S.IsDerivedFrom(SourceType, DestType)))) 4512 TryConstructorInitialization(S, Entity, Kind, Args, 4513 Entity.getType(), *this); 4514 // - Otherwise (i.e., for the remaining copy-initialization cases), 4515 // user-defined conversion sequences that can convert from the source 4516 // type to the destination type or (when a conversion function is 4517 // used) to a derived class thereof are enumerated as described in 4518 // 13.3.1.4, and the best one is chosen through overload resolution 4519 // (13.3). 4520 else 4521 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 4522 return; 4523 } 4524 4525 if (Args.size() > 1) { 4526 SetFailed(FK_TooManyInitsForScalar); 4527 return; 4528 } 4529 assert(Args.size() == 1 && "Zero-argument case handled above"); 4530 4531 // - Otherwise, if the source type is a (possibly cv-qualified) class 4532 // type, conversion functions are considered. 4533 if (!SourceType.isNull() && SourceType->isRecordType()) { 4534 TryUserDefinedConversion(S, Entity, Kind, Initializer, *this); 4535 MaybeProduceObjCObject(S, *this, Entity); 4536 return; 4537 } 4538 4539 // - Otherwise, the initial value of the object being initialized is the 4540 // (possibly converted) value of the initializer expression. Standard 4541 // conversions (Clause 4) will be used, if necessary, to convert the 4542 // initializer expression to the cv-unqualified version of the 4543 // destination type; no user-defined conversions are considered. 4544 4545 ImplicitConversionSequence ICS 4546 = S.TryImplicitConversion(Initializer, Entity.getType(), 4547 /*SuppressUserConversions*/true, 4548 /*AllowExplicitConversions*/ false, 4549 /*InOverloadResolution*/ false, 4550 /*CStyle=*/Kind.isCStyleOrFunctionalCast(), 4551 allowObjCWritebackConversion); 4552 4553 if (ICS.isStandard() && 4554 ICS.Standard.Second == ICK_Writeback_Conversion) { 4555 // Objective-C ARC writeback conversion. 4556 4557 // We should copy unless we're passing to an argument explicitly 4558 // marked 'out'. 4559 bool ShouldCopy = true; 4560 if (ParmVarDecl *Param = cast_or_null<ParmVarDecl>(Entity.getDecl())) 4561 ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out); 4562 4563 // If there was an lvalue adjustment, add it as a separate conversion. 4564 if (ICS.Standard.First == ICK_Array_To_Pointer || 4565 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 4566 ImplicitConversionSequence LvalueICS; 4567 LvalueICS.setStandard(); 4568 LvalueICS.Standard.setAsIdentityConversion(); 4569 LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0)); 4570 LvalueICS.Standard.First = ICS.Standard.First; 4571 AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0)); 4572 } 4573 4574 AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy); 4575 } else if (ICS.isBad()) { 4576 DeclAccessPair dap; 4577 if (Initializer->getType() == Context.OverloadTy && 4578 !S.ResolveAddressOfOverloadedFunction(Initializer 4579 , DestType, false, dap)) 4580 SetFailed(InitializationSequence::FK_AddressOfOverloadFailed); 4581 else 4582 SetFailed(InitializationSequence::FK_ConversionFailed); 4583 } else { 4584 AddConversionSequenceStep(ICS, Entity.getType()); 4585 4586 MaybeProduceObjCObject(S, *this, Entity); 4587 } 4588} 4589 4590InitializationSequence::~InitializationSequence() { 4591 for (SmallVectorImpl<Step>::iterator Step = Steps.begin(), 4592 StepEnd = Steps.end(); 4593 Step != StepEnd; ++Step) 4594 Step->Destroy(); 4595} 4596 4597//===----------------------------------------------------------------------===// 4598// Perform initialization 4599//===----------------------------------------------------------------------===// 4600static Sema::AssignmentAction 4601getAssignmentAction(const InitializedEntity &Entity) { 4602 switch(Entity.getKind()) { 4603 case InitializedEntity::EK_Variable: 4604 case InitializedEntity::EK_New: 4605 case InitializedEntity::EK_Exception: 4606 case InitializedEntity::EK_Base: 4607 case InitializedEntity::EK_Delegating: 4608 return Sema::AA_Initializing; 4609 4610 case InitializedEntity::EK_Parameter: 4611 if (Entity.getDecl() && 4612 isa<ObjCMethodDecl>(Entity.getDecl()->getDeclContext())) 4613 return Sema::AA_Sending; 4614 4615 return Sema::AA_Passing; 4616 4617 case InitializedEntity::EK_Result: 4618 return Sema::AA_Returning; 4619 4620 case InitializedEntity::EK_Temporary: 4621 // FIXME: Can we tell apart casting vs. converting? 4622 return Sema::AA_Casting; 4623 4624 case InitializedEntity::EK_Member: 4625 case InitializedEntity::EK_ArrayElement: 4626 case InitializedEntity::EK_VectorElement: 4627 case InitializedEntity::EK_ComplexElement: 4628 case InitializedEntity::EK_BlockElement: 4629 case InitializedEntity::EK_LambdaCapture: 4630 case InitializedEntity::EK_CompoundLiteralInit: 4631 return Sema::AA_Initializing; 4632 } 4633 4634 llvm_unreachable("Invalid EntityKind!"); 4635} 4636 4637/// \brief Whether we should bind a created object as a temporary when 4638/// initializing the given entity. 4639static bool shouldBindAsTemporary(const InitializedEntity &Entity) { 4640 switch (Entity.getKind()) { 4641 case InitializedEntity::EK_ArrayElement: 4642 case InitializedEntity::EK_Member: 4643 case InitializedEntity::EK_Result: 4644 case InitializedEntity::EK_New: 4645 case InitializedEntity::EK_Variable: 4646 case InitializedEntity::EK_Base: 4647 case InitializedEntity::EK_Delegating: 4648 case InitializedEntity::EK_VectorElement: 4649 case InitializedEntity::EK_ComplexElement: 4650 case InitializedEntity::EK_Exception: 4651 case InitializedEntity::EK_BlockElement: 4652 case InitializedEntity::EK_LambdaCapture: 4653 case InitializedEntity::EK_CompoundLiteralInit: 4654 return false; 4655 4656 case InitializedEntity::EK_Parameter: 4657 case InitializedEntity::EK_Temporary: 4658 return true; 4659 } 4660 4661 llvm_unreachable("missed an InitializedEntity kind?"); 4662} 4663 4664/// \brief Whether the given entity, when initialized with an object 4665/// created for that initialization, requires destruction. 4666static bool shouldDestroyTemporary(const InitializedEntity &Entity) { 4667 switch (Entity.getKind()) { 4668 case InitializedEntity::EK_Result: 4669 case InitializedEntity::EK_New: 4670 case InitializedEntity::EK_Base: 4671 case InitializedEntity::EK_Delegating: 4672 case InitializedEntity::EK_VectorElement: 4673 case InitializedEntity::EK_ComplexElement: 4674 case InitializedEntity::EK_BlockElement: 4675 case InitializedEntity::EK_LambdaCapture: 4676 return false; 4677 4678 case InitializedEntity::EK_Member: 4679 case InitializedEntity::EK_Variable: 4680 case InitializedEntity::EK_Parameter: 4681 case InitializedEntity::EK_Temporary: 4682 case InitializedEntity::EK_ArrayElement: 4683 case InitializedEntity::EK_Exception: 4684 case InitializedEntity::EK_CompoundLiteralInit: 4685 return true; 4686 } 4687 4688 llvm_unreachable("missed an InitializedEntity kind?"); 4689} 4690 4691/// \brief Look for copy and move constructors and constructor templates, for 4692/// copying an object via direct-initialization (per C++11 [dcl.init]p16). 4693static void LookupCopyAndMoveConstructors(Sema &S, 4694 OverloadCandidateSet &CandidateSet, 4695 CXXRecordDecl *Class, 4696 Expr *CurInitExpr) { 4697 DeclContext::lookup_result R = S.LookupConstructors(Class); 4698 // The container holding the constructors can under certain conditions 4699 // be changed while iterating (e.g. because of deserialization). 4700 // To be safe we copy the lookup results to a new container. 4701 SmallVector<NamedDecl*, 16> Ctors(R.begin(), R.end()); 4702 for (SmallVector<NamedDecl*, 16>::iterator 4703 CI = Ctors.begin(), CE = Ctors.end(); CI != CE; ++CI) { 4704 NamedDecl *D = *CI; 4705 CXXConstructorDecl *Constructor = 0; 4706 4707 if ((Constructor = dyn_cast<CXXConstructorDecl>(D))) { 4708 // Handle copy/moveconstructors, only. 4709 if (!Constructor || Constructor->isInvalidDecl() || 4710 !Constructor->isCopyOrMoveConstructor() || 4711 !Constructor->isConvertingConstructor(/*AllowExplicit=*/true)) 4712 continue; 4713 4714 DeclAccessPair FoundDecl 4715 = DeclAccessPair::make(Constructor, Constructor->getAccess()); 4716 S.AddOverloadCandidate(Constructor, FoundDecl, 4717 CurInitExpr, CandidateSet); 4718 continue; 4719 } 4720 4721 // Handle constructor templates. 4722 FunctionTemplateDecl *ConstructorTmpl = cast<FunctionTemplateDecl>(D); 4723 if (ConstructorTmpl->isInvalidDecl()) 4724 continue; 4725 4726 Constructor = cast<CXXConstructorDecl>( 4727 ConstructorTmpl->getTemplatedDecl()); 4728 if (!Constructor->isConvertingConstructor(/*AllowExplicit=*/true)) 4729 continue; 4730 4731 // FIXME: Do we need to limit this to copy-constructor-like 4732 // candidates? 4733 DeclAccessPair FoundDecl 4734 = DeclAccessPair::make(ConstructorTmpl, ConstructorTmpl->getAccess()); 4735 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 0, 4736 CurInitExpr, CandidateSet, true); 4737 } 4738} 4739 4740/// \brief Get the location at which initialization diagnostics should appear. 4741static SourceLocation getInitializationLoc(const InitializedEntity &Entity, 4742 Expr *Initializer) { 4743 switch (Entity.getKind()) { 4744 case InitializedEntity::EK_Result: 4745 return Entity.getReturnLoc(); 4746 4747 case InitializedEntity::EK_Exception: 4748 return Entity.getThrowLoc(); 4749 4750 case InitializedEntity::EK_Variable: 4751 return Entity.getDecl()->getLocation(); 4752 4753 case InitializedEntity::EK_LambdaCapture: 4754 return Entity.getCaptureLoc(); 4755 4756 case InitializedEntity::EK_ArrayElement: 4757 case InitializedEntity::EK_Member: 4758 case InitializedEntity::EK_Parameter: 4759 case InitializedEntity::EK_Temporary: 4760 case InitializedEntity::EK_New: 4761 case InitializedEntity::EK_Base: 4762 case InitializedEntity::EK_Delegating: 4763 case InitializedEntity::EK_VectorElement: 4764 case InitializedEntity::EK_ComplexElement: 4765 case InitializedEntity::EK_BlockElement: 4766 case InitializedEntity::EK_CompoundLiteralInit: 4767 return Initializer->getLocStart(); 4768 } 4769 llvm_unreachable("missed an InitializedEntity kind?"); 4770} 4771 4772/// \brief Make a (potentially elidable) temporary copy of the object 4773/// provided by the given initializer by calling the appropriate copy 4774/// constructor. 4775/// 4776/// \param S The Sema object used for type-checking. 4777/// 4778/// \param T The type of the temporary object, which must either be 4779/// the type of the initializer expression or a superclass thereof. 4780/// 4781/// \param Entity The entity being initialized. 4782/// 4783/// \param CurInit The initializer expression. 4784/// 4785/// \param IsExtraneousCopy Whether this is an "extraneous" copy that 4786/// is permitted in C++03 (but not C++0x) when binding a reference to 4787/// an rvalue. 4788/// 4789/// \returns An expression that copies the initializer expression into 4790/// a temporary object, or an error expression if a copy could not be 4791/// created. 4792static ExprResult CopyObject(Sema &S, 4793 QualType T, 4794 const InitializedEntity &Entity, 4795 ExprResult CurInit, 4796 bool IsExtraneousCopy) { 4797 // Determine which class type we're copying to. 4798 Expr *CurInitExpr = (Expr *)CurInit.get(); 4799 CXXRecordDecl *Class = 0; 4800 if (const RecordType *Record = T->getAs<RecordType>()) 4801 Class = cast<CXXRecordDecl>(Record->getDecl()); 4802 if (!Class) 4803 return CurInit; 4804 4805 // C++0x [class.copy]p32: 4806 // When certain criteria are met, an implementation is allowed to 4807 // omit the copy/move construction of a class object, even if the 4808 // copy/move constructor and/or destructor for the object have 4809 // side effects. [...] 4810 // - when a temporary class object that has not been bound to a 4811 // reference (12.2) would be copied/moved to a class object 4812 // with the same cv-unqualified type, the copy/move operation 4813 // can be omitted by constructing the temporary object 4814 // directly into the target of the omitted copy/move 4815 // 4816 // Note that the other three bullets are handled elsewhere. Copy 4817 // elision for return statements and throw expressions are handled as part 4818 // of constructor initialization, while copy elision for exception handlers 4819 // is handled by the run-time. 4820 bool Elidable = CurInitExpr->isTemporaryObject(S.Context, Class); 4821 SourceLocation Loc = getInitializationLoc(Entity, CurInit.get()); 4822 4823 // Make sure that the type we are copying is complete. 4824 if (S.RequireCompleteType(Loc, T, diag::err_temp_copy_incomplete)) 4825 return CurInit; 4826 4827 // Perform overload resolution using the class's copy/move constructors. 4828 // Only consider constructors and constructor templates. Per 4829 // C++0x [dcl.init]p16, second bullet to class types, this initialization 4830 // is direct-initialization. 4831 OverloadCandidateSet CandidateSet(Loc); 4832 LookupCopyAndMoveConstructors(S, CandidateSet, Class, CurInitExpr); 4833 4834 bool HadMultipleCandidates = (CandidateSet.size() > 1); 4835 4836 OverloadCandidateSet::iterator Best; 4837 switch (CandidateSet.BestViableFunction(S, Loc, Best)) { 4838 case OR_Success: 4839 break; 4840 4841 case OR_No_Viable_Function: 4842 S.Diag(Loc, IsExtraneousCopy && !S.isSFINAEContext() 4843 ? diag::ext_rvalue_to_reference_temp_copy_no_viable 4844 : diag::err_temp_copy_no_viable) 4845 << (int)Entity.getKind() << CurInitExpr->getType() 4846 << CurInitExpr->getSourceRange(); 4847 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr); 4848 if (!IsExtraneousCopy || S.isSFINAEContext()) 4849 return ExprError(); 4850 return CurInit; 4851 4852 case OR_Ambiguous: 4853 S.Diag(Loc, diag::err_temp_copy_ambiguous) 4854 << (int)Entity.getKind() << CurInitExpr->getType() 4855 << CurInitExpr->getSourceRange(); 4856 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr); 4857 return ExprError(); 4858 4859 case OR_Deleted: 4860 S.Diag(Loc, diag::err_temp_copy_deleted) 4861 << (int)Entity.getKind() << CurInitExpr->getType() 4862 << CurInitExpr->getSourceRange(); 4863 S.NoteDeletedFunction(Best->Function); 4864 return ExprError(); 4865 } 4866 4867 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function); 4868 SmallVector<Expr*, 8> ConstructorArgs; 4869 CurInit.release(); // Ownership transferred into MultiExprArg, below. 4870 4871 S.CheckConstructorAccess(Loc, Constructor, Entity, 4872 Best->FoundDecl.getAccess(), IsExtraneousCopy); 4873 4874 if (IsExtraneousCopy) { 4875 // If this is a totally extraneous copy for C++03 reference 4876 // binding purposes, just return the original initialization 4877 // expression. We don't generate an (elided) copy operation here 4878 // because doing so would require us to pass down a flag to avoid 4879 // infinite recursion, where each step adds another extraneous, 4880 // elidable copy. 4881 4882 // Instantiate the default arguments of any extra parameters in 4883 // the selected copy constructor, as if we were going to create a 4884 // proper call to the copy constructor. 4885 for (unsigned I = 1, N = Constructor->getNumParams(); I != N; ++I) { 4886 ParmVarDecl *Parm = Constructor->getParamDecl(I); 4887 if (S.RequireCompleteType(Loc, Parm->getType(), 4888 diag::err_call_incomplete_argument)) 4889 break; 4890 4891 // Build the default argument expression; we don't actually care 4892 // if this succeeds or not, because this routine will complain 4893 // if there was a problem. 4894 S.BuildCXXDefaultArgExpr(Loc, Constructor, Parm); 4895 } 4896 4897 return S.Owned(CurInitExpr); 4898 } 4899 4900 // Determine the arguments required to actually perform the 4901 // constructor call (we might have derived-to-base conversions, or 4902 // the copy constructor may have default arguments). 4903 if (S.CompleteConstructorCall(Constructor, CurInitExpr, Loc, ConstructorArgs)) 4904 return ExprError(); 4905 4906 // Actually perform the constructor call. 4907 CurInit = S.BuildCXXConstructExpr(Loc, T, Constructor, Elidable, 4908 ConstructorArgs, 4909 HadMultipleCandidates, 4910 /*ListInit*/ false, 4911 /*ZeroInit*/ false, 4912 CXXConstructExpr::CK_Complete, 4913 SourceRange()); 4914 4915 // If we're supposed to bind temporaries, do so. 4916 if (!CurInit.isInvalid() && shouldBindAsTemporary(Entity)) 4917 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 4918 return CurInit; 4919} 4920 4921/// \brief Check whether elidable copy construction for binding a reference to 4922/// a temporary would have succeeded if we were building in C++98 mode, for 4923/// -Wc++98-compat. 4924static void CheckCXX98CompatAccessibleCopy(Sema &S, 4925 const InitializedEntity &Entity, 4926 Expr *CurInitExpr) { 4927 assert(S.getLangOpts().CPlusPlus11); 4928 4929 const RecordType *Record = CurInitExpr->getType()->getAs<RecordType>(); 4930 if (!Record) 4931 return; 4932 4933 SourceLocation Loc = getInitializationLoc(Entity, CurInitExpr); 4934 if (S.Diags.getDiagnosticLevel(diag::warn_cxx98_compat_temp_copy, Loc) 4935 == DiagnosticsEngine::Ignored) 4936 return; 4937 4938 // Find constructors which would have been considered. 4939 OverloadCandidateSet CandidateSet(Loc); 4940 LookupCopyAndMoveConstructors( 4941 S, CandidateSet, cast<CXXRecordDecl>(Record->getDecl()), CurInitExpr); 4942 4943 // Perform overload resolution. 4944 OverloadCandidateSet::iterator Best; 4945 OverloadingResult OR = CandidateSet.BestViableFunction(S, Loc, Best); 4946 4947 PartialDiagnostic Diag = S.PDiag(diag::warn_cxx98_compat_temp_copy) 4948 << OR << (int)Entity.getKind() << CurInitExpr->getType() 4949 << CurInitExpr->getSourceRange(); 4950 4951 switch (OR) { 4952 case OR_Success: 4953 S.CheckConstructorAccess(Loc, cast<CXXConstructorDecl>(Best->Function), 4954 Entity, Best->FoundDecl.getAccess(), Diag); 4955 // FIXME: Check default arguments as far as that's possible. 4956 break; 4957 4958 case OR_No_Viable_Function: 4959 S.Diag(Loc, Diag); 4960 CandidateSet.NoteCandidates(S, OCD_AllCandidates, CurInitExpr); 4961 break; 4962 4963 case OR_Ambiguous: 4964 S.Diag(Loc, Diag); 4965 CandidateSet.NoteCandidates(S, OCD_ViableCandidates, CurInitExpr); 4966 break; 4967 4968 case OR_Deleted: 4969 S.Diag(Loc, Diag); 4970 S.NoteDeletedFunction(Best->Function); 4971 break; 4972 } 4973} 4974 4975void InitializationSequence::PrintInitLocationNote(Sema &S, 4976 const InitializedEntity &Entity) { 4977 if (Entity.getKind() == InitializedEntity::EK_Parameter && Entity.getDecl()) { 4978 if (Entity.getDecl()->getLocation().isInvalid()) 4979 return; 4980 4981 if (Entity.getDecl()->getDeclName()) 4982 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_named_here) 4983 << Entity.getDecl()->getDeclName(); 4984 else 4985 S.Diag(Entity.getDecl()->getLocation(), diag::note_parameter_here); 4986 } 4987} 4988 4989static bool isReferenceBinding(const InitializationSequence::Step &s) { 4990 return s.Kind == InitializationSequence::SK_BindReference || 4991 s.Kind == InitializationSequence::SK_BindReferenceToTemporary; 4992} 4993 4994/// Returns true if the parameters describe a constructor initialization of 4995/// an explicit temporary object, e.g. "Point(x, y)". 4996static bool isExplicitTemporary(const InitializedEntity &Entity, 4997 const InitializationKind &Kind, 4998 unsigned NumArgs) { 4999 switch (Entity.getKind()) { 5000 case InitializedEntity::EK_Temporary: 5001 case InitializedEntity::EK_CompoundLiteralInit: 5002 break; 5003 default: 5004 return false; 5005 } 5006 5007 switch (Kind.getKind()) { 5008 case InitializationKind::IK_DirectList: 5009 return true; 5010 // FIXME: Hack to work around cast weirdness. 5011 case InitializationKind::IK_Direct: 5012 case InitializationKind::IK_Value: 5013 return NumArgs != 1; 5014 default: 5015 return false; 5016 } 5017} 5018 5019static ExprResult 5020PerformConstructorInitialization(Sema &S, 5021 const InitializedEntity &Entity, 5022 const InitializationKind &Kind, 5023 MultiExprArg Args, 5024 const InitializationSequence::Step& Step, 5025 bool &ConstructorInitRequiresZeroInit, 5026 bool IsListInitialization) { 5027 unsigned NumArgs = Args.size(); 5028 CXXConstructorDecl *Constructor 5029 = cast<CXXConstructorDecl>(Step.Function.Function); 5030 bool HadMultipleCandidates = Step.Function.HadMultipleCandidates; 5031 5032 // Build a call to the selected constructor. 5033 SmallVector<Expr*, 8> ConstructorArgs; 5034 SourceLocation Loc = (Kind.isCopyInit() && Kind.getEqualLoc().isValid()) 5035 ? Kind.getEqualLoc() 5036 : Kind.getLocation(); 5037 5038 if (Kind.getKind() == InitializationKind::IK_Default) { 5039 // Force even a trivial, implicit default constructor to be 5040 // semantically checked. We do this explicitly because we don't build 5041 // the definition for completely trivial constructors. 5042 assert(Constructor->getParent() && "No parent class for constructor."); 5043 if (Constructor->isDefaulted() && Constructor->isDefaultConstructor() && 5044 Constructor->isTrivial() && !Constructor->isUsed(false)) 5045 S.DefineImplicitDefaultConstructor(Loc, Constructor); 5046 } 5047 5048 ExprResult CurInit = S.Owned((Expr *)0); 5049 5050 // C++ [over.match.copy]p1: 5051 // - When initializing a temporary to be bound to the first parameter 5052 // of a constructor that takes a reference to possibly cv-qualified 5053 // T as its first argument, called with a single argument in the 5054 // context of direct-initialization, explicit conversion functions 5055 // are also considered. 5056 bool AllowExplicitConv = Kind.AllowExplicit() && !Kind.isCopyInit() && 5057 Args.size() == 1 && 5058 Constructor->isCopyOrMoveConstructor(); 5059 5060 // Determine the arguments required to actually perform the constructor 5061 // call. 5062 if (S.CompleteConstructorCall(Constructor, Args, 5063 Loc, ConstructorArgs, 5064 AllowExplicitConv, 5065 IsListInitialization)) 5066 return ExprError(); 5067 5068 5069 if (isExplicitTemporary(Entity, Kind, NumArgs)) { 5070 // An explicitly-constructed temporary, e.g., X(1, 2). 5071 S.MarkFunctionReferenced(Loc, Constructor); 5072 if (S.DiagnoseUseOfDecl(Constructor, Loc)) 5073 return ExprError(); 5074 5075 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo(); 5076 if (!TSInfo) 5077 TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc); 5078 SourceRange ParenRange; 5079 if (Kind.getKind() != InitializationKind::IK_DirectList) 5080 ParenRange = Kind.getParenRange(); 5081 5082 CurInit = S.Owned( 5083 new (S.Context) CXXTemporaryObjectExpr(S.Context, Constructor, 5084 TSInfo, ConstructorArgs, 5085 ParenRange, IsListInitialization, 5086 HadMultipleCandidates, 5087 ConstructorInitRequiresZeroInit)); 5088 } else { 5089 CXXConstructExpr::ConstructionKind ConstructKind = 5090 CXXConstructExpr::CK_Complete; 5091 5092 if (Entity.getKind() == InitializedEntity::EK_Base) { 5093 ConstructKind = Entity.getBaseSpecifier()->isVirtual() ? 5094 CXXConstructExpr::CK_VirtualBase : 5095 CXXConstructExpr::CK_NonVirtualBase; 5096 } else if (Entity.getKind() == InitializedEntity::EK_Delegating) { 5097 ConstructKind = CXXConstructExpr::CK_Delegating; 5098 } 5099 5100 // Only get the parenthesis range if it is a direct construction. 5101 SourceRange parenRange = 5102 Kind.getKind() == InitializationKind::IK_Direct ? 5103 Kind.getParenRange() : SourceRange(); 5104 5105 // If the entity allows NRVO, mark the construction as elidable 5106 // unconditionally. 5107 if (Entity.allowsNRVO()) 5108 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), 5109 Constructor, /*Elidable=*/true, 5110 ConstructorArgs, 5111 HadMultipleCandidates, 5112 IsListInitialization, 5113 ConstructorInitRequiresZeroInit, 5114 ConstructKind, 5115 parenRange); 5116 else 5117 CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(), 5118 Constructor, 5119 ConstructorArgs, 5120 HadMultipleCandidates, 5121 IsListInitialization, 5122 ConstructorInitRequiresZeroInit, 5123 ConstructKind, 5124 parenRange); 5125 } 5126 if (CurInit.isInvalid()) 5127 return ExprError(); 5128 5129 // Only check access if all of that succeeded. 5130 S.CheckConstructorAccess(Loc, Constructor, Entity, 5131 Step.Function.FoundDecl.getAccess()); 5132 if (S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc)) 5133 return ExprError(); 5134 5135 if (shouldBindAsTemporary(Entity)) 5136 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 5137 5138 return CurInit; 5139} 5140 5141/// Determine whether the specified InitializedEntity definitely has a lifetime 5142/// longer than the current full-expression. Conservatively returns false if 5143/// it's unclear. 5144static bool 5145InitializedEntityOutlivesFullExpression(const InitializedEntity &Entity) { 5146 const InitializedEntity *Top = &Entity; 5147 while (Top->getParent()) 5148 Top = Top->getParent(); 5149 5150 switch (Top->getKind()) { 5151 case InitializedEntity::EK_Variable: 5152 case InitializedEntity::EK_Result: 5153 case InitializedEntity::EK_Exception: 5154 case InitializedEntity::EK_Member: 5155 case InitializedEntity::EK_New: 5156 case InitializedEntity::EK_Base: 5157 case InitializedEntity::EK_Delegating: 5158 return true; 5159 5160 case InitializedEntity::EK_ArrayElement: 5161 case InitializedEntity::EK_VectorElement: 5162 case InitializedEntity::EK_BlockElement: 5163 case InitializedEntity::EK_ComplexElement: 5164 // Could not determine what the full initialization is. Assume it might not 5165 // outlive the full-expression. 5166 return false; 5167 5168 case InitializedEntity::EK_Parameter: 5169 case InitializedEntity::EK_Temporary: 5170 case InitializedEntity::EK_LambdaCapture: 5171 case InitializedEntity::EK_CompoundLiteralInit: 5172 // The entity being initialized might not outlive the full-expression. 5173 return false; 5174 } 5175 5176 llvm_unreachable("unknown entity kind"); 5177} 5178 5179/// Determine the declaration which an initialized entity ultimately refers to, 5180/// for the purpose of lifetime-extending a temporary bound to a reference in 5181/// the initialization of \p Entity. 5182static const ValueDecl * 5183getDeclForTemporaryLifetimeExtension(const InitializedEntity &Entity, 5184 const ValueDecl *FallbackDecl = 0) { 5185 // C++11 [class.temporary]p5: 5186 switch (Entity.getKind()) { 5187 case InitializedEntity::EK_Variable: 5188 // The temporary [...] persists for the lifetime of the reference 5189 return Entity.getDecl(); 5190 5191 case InitializedEntity::EK_Member: 5192 // For subobjects, we look at the complete object. 5193 if (Entity.getParent()) 5194 return getDeclForTemporaryLifetimeExtension(*Entity.getParent(), 5195 Entity.getDecl()); 5196 5197 // except: 5198 // -- A temporary bound to a reference member in a constructor's 5199 // ctor-initializer persists until the constructor exits. 5200 return Entity.getDecl(); 5201 5202 case InitializedEntity::EK_Parameter: 5203 // -- A temporary bound to a reference parameter in a function call 5204 // persists until the completion of the full-expression containing 5205 // the call. 5206 case InitializedEntity::EK_Result: 5207 // -- The lifetime of a temporary bound to the returned value in a 5208 // function return statement is not extended; the temporary is 5209 // destroyed at the end of the full-expression in the return statement. 5210 case InitializedEntity::EK_New: 5211 // -- A temporary bound to a reference in a new-initializer persists 5212 // until the completion of the full-expression containing the 5213 // new-initializer. 5214 return 0; 5215 5216 case InitializedEntity::EK_Temporary: 5217 case InitializedEntity::EK_CompoundLiteralInit: 5218 // We don't yet know the storage duration of the surrounding temporary. 5219 // Assume it's got full-expression duration for now, it will patch up our 5220 // storage duration if that's not correct. 5221 return 0; 5222 5223 case InitializedEntity::EK_ArrayElement: 5224 // For subobjects, we look at the complete object. 5225 return getDeclForTemporaryLifetimeExtension(*Entity.getParent(), 5226 FallbackDecl); 5227 5228 case InitializedEntity::EK_Base: 5229 case InitializedEntity::EK_Delegating: 5230 // We can reach this case for aggregate initialization in a constructor: 5231 // struct A { int &&r; }; 5232 // struct B : A { B() : A{0} {} }; 5233 // In this case, use the innermost field decl as the context. 5234 return FallbackDecl; 5235 5236 case InitializedEntity::EK_BlockElement: 5237 case InitializedEntity::EK_LambdaCapture: 5238 case InitializedEntity::EK_Exception: 5239 case InitializedEntity::EK_VectorElement: 5240 case InitializedEntity::EK_ComplexElement: 5241 llvm_unreachable("should not materialize a temporary to initialize this"); 5242 } 5243 llvm_unreachable("unknown entity kind"); 5244} 5245 5246static void performLifetimeExtension(Expr *Init, const ValueDecl *ExtendingD); 5247 5248/// Update a glvalue expression that is used as the initializer of a reference 5249/// to note that its lifetime is extended. 5250static void performReferenceExtension(Expr *Init, const ValueDecl *ExtendingD) { 5251 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 5252 if (ILE->getNumInits() == 1 && ILE->isGLValue()) { 5253 // This is just redundant braces around an initializer. Step over it. 5254 Init = ILE->getInit(0); 5255 } 5256 } 5257 5258 if (MaterializeTemporaryExpr *ME = dyn_cast<MaterializeTemporaryExpr>(Init)) { 5259 // Update the storage duration of the materialized temporary. 5260 // FIXME: Rebuild the expression instead of mutating it. 5261 ME->setExtendingDecl(ExtendingD); 5262 performLifetimeExtension(ME->GetTemporaryExpr(), ExtendingD); 5263 } 5264} 5265 5266/// Update a prvalue expression that is going to be materialized as a 5267/// lifetime-extended temporary. 5268static void performLifetimeExtension(Expr *Init, const ValueDecl *ExtendingD) { 5269 // Dig out the expression which constructs the extended temporary. 5270 SmallVector<const Expr *, 2> CommaLHSs; 5271 SmallVector<SubobjectAdjustment, 2> Adjustments; 5272 Init = const_cast<Expr *>( 5273 Init->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments)); 5274 5275 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 5276 if (ILE->initializesStdInitializerList() || ILE->getType()->isArrayType()) { 5277 // FIXME: If this is an InitListExpr which creates a std::initializer_list 5278 // object, we also need to lifetime-extend the underlying array 5279 // itself. Fix the representation to explicitly materialize an 5280 // array temporary so we can model this properly. 5281 for (unsigned I = 0, N = ILE->getNumInits(); I != N; ++I) 5282 performLifetimeExtension(ILE->getInit(I), ExtendingD); 5283 return; 5284 } 5285 5286 CXXRecordDecl *RD = ILE->getType()->getAsCXXRecordDecl(); 5287 if (RD) { 5288 assert(RD->isAggregate() && "aggregate init on non-aggregate"); 5289 5290 // If we lifetime-extend a braced initializer which is initializing an 5291 // aggregate, and that aggregate contains reference members which are 5292 // bound to temporaries, those temporaries are also lifetime-extended. 5293 if (RD->isUnion() && ILE->getInitializedFieldInUnion() && 5294 ILE->getInitializedFieldInUnion()->getType()->isReferenceType()) 5295 performReferenceExtension(ILE->getInit(0), ExtendingD); 5296 else { 5297 unsigned Index = 0; 5298 for (RecordDecl::field_iterator I = RD->field_begin(), 5299 E = RD->field_end(); 5300 I != E; ++I) { 5301 if (I->isUnnamedBitfield()) 5302 continue; 5303 if (I->getType()->isReferenceType()) 5304 performReferenceExtension(ILE->getInit(Index), ExtendingD); 5305 else if (isa<InitListExpr>(ILE->getInit(Index))) 5306 // This may be either aggregate-initialization of a member or 5307 // initialization of a std::initializer_list object. Either way, 5308 // we should recursively lifetime-extend that initializer. 5309 performLifetimeExtension(ILE->getInit(Index), ExtendingD); 5310 ++Index; 5311 } 5312 } 5313 } 5314 } 5315} 5316 5317ExprResult 5318InitializationSequence::Perform(Sema &S, 5319 const InitializedEntity &Entity, 5320 const InitializationKind &Kind, 5321 MultiExprArg Args, 5322 QualType *ResultType) { 5323 if (Failed()) { 5324 Diagnose(S, Entity, Kind, Args); 5325 return ExprError(); 5326 } 5327 5328 if (getKind() == DependentSequence) { 5329 // If the declaration is a non-dependent, incomplete array type 5330 // that has an initializer, then its type will be completed once 5331 // the initializer is instantiated. 5332 if (ResultType && !Entity.getType()->isDependentType() && 5333 Args.size() == 1) { 5334 QualType DeclType = Entity.getType(); 5335 if (const IncompleteArrayType *ArrayT 5336 = S.Context.getAsIncompleteArrayType(DeclType)) { 5337 // FIXME: We don't currently have the ability to accurately 5338 // compute the length of an initializer list without 5339 // performing full type-checking of the initializer list 5340 // (since we have to determine where braces are implicitly 5341 // introduced and such). So, we fall back to making the array 5342 // type a dependently-sized array type with no specified 5343 // bound. 5344 if (isa<InitListExpr>((Expr *)Args[0])) { 5345 SourceRange Brackets; 5346 5347 // Scavange the location of the brackets from the entity, if we can. 5348 if (DeclaratorDecl *DD = Entity.getDecl()) { 5349 if (TypeSourceInfo *TInfo = DD->getTypeSourceInfo()) { 5350 TypeLoc TL = TInfo->getTypeLoc(); 5351 if (IncompleteArrayTypeLoc ArrayLoc = 5352 TL.getAs<IncompleteArrayTypeLoc>()) 5353 Brackets = ArrayLoc.getBracketsRange(); 5354 } 5355 } 5356 5357 *ResultType 5358 = S.Context.getDependentSizedArrayType(ArrayT->getElementType(), 5359 /*NumElts=*/0, 5360 ArrayT->getSizeModifier(), 5361 ArrayT->getIndexTypeCVRQualifiers(), 5362 Brackets); 5363 } 5364 5365 } 5366 } 5367 if (Kind.getKind() == InitializationKind::IK_Direct && 5368 !Kind.isExplicitCast()) { 5369 // Rebuild the ParenListExpr. 5370 SourceRange ParenRange = Kind.getParenRange(); 5371 return S.ActOnParenListExpr(ParenRange.getBegin(), ParenRange.getEnd(), 5372 Args); 5373 } 5374 assert(Kind.getKind() == InitializationKind::IK_Copy || 5375 Kind.isExplicitCast() || 5376 Kind.getKind() == InitializationKind::IK_DirectList); 5377 return ExprResult(Args[0]); 5378 } 5379 5380 // No steps means no initialization. 5381 if (Steps.empty()) 5382 return S.Owned((Expr *)0); 5383 5384 if (S.getLangOpts().CPlusPlus11 && Entity.getType()->isReferenceType() && 5385 Args.size() == 1 && isa<InitListExpr>(Args[0]) && 5386 Entity.getKind() != InitializedEntity::EK_Parameter) { 5387 // Produce a C++98 compatibility warning if we are initializing a reference 5388 // from an initializer list. For parameters, we produce a better warning 5389 // elsewhere. 5390 Expr *Init = Args[0]; 5391 S.Diag(Init->getLocStart(), diag::warn_cxx98_compat_reference_list_init) 5392 << Init->getSourceRange(); 5393 } 5394 5395 // Diagnose cases where we initialize a pointer to an array temporary, and the 5396 // pointer obviously outlives the temporary. 5397 if (Args.size() == 1 && Args[0]->getType()->isArrayType() && 5398 Entity.getType()->isPointerType() && 5399 InitializedEntityOutlivesFullExpression(Entity)) { 5400 Expr *Init = Args[0]; 5401 Expr::LValueClassification Kind = Init->ClassifyLValue(S.Context); 5402 if (Kind == Expr::LV_ClassTemporary || Kind == Expr::LV_ArrayTemporary) 5403 S.Diag(Init->getLocStart(), diag::warn_temporary_array_to_pointer_decay) 5404 << Init->getSourceRange(); 5405 } 5406 5407 QualType DestType = Entity.getType().getNonReferenceType(); 5408 // FIXME: Ugly hack around the fact that Entity.getType() is not 5409 // the same as Entity.getDecl()->getType() in cases involving type merging, 5410 // and we want latter when it makes sense. 5411 if (ResultType) 5412 *ResultType = Entity.getDecl() ? Entity.getDecl()->getType() : 5413 Entity.getType(); 5414 5415 ExprResult CurInit = S.Owned((Expr *)0); 5416 5417 // For initialization steps that start with a single initializer, 5418 // grab the only argument out the Args and place it into the "current" 5419 // initializer. 5420 switch (Steps.front().Kind) { 5421 case SK_ResolveAddressOfOverloadedFunction: 5422 case SK_CastDerivedToBaseRValue: 5423 case SK_CastDerivedToBaseXValue: 5424 case SK_CastDerivedToBaseLValue: 5425 case SK_BindReference: 5426 case SK_BindReferenceToTemporary: 5427 case SK_ExtraneousCopyToTemporary: 5428 case SK_UserConversion: 5429 case SK_QualificationConversionLValue: 5430 case SK_QualificationConversionXValue: 5431 case SK_QualificationConversionRValue: 5432 case SK_LValueToRValue: 5433 case SK_ConversionSequence: 5434 case SK_ListInitialization: 5435 case SK_UnwrapInitList: 5436 case SK_RewrapInitList: 5437 case SK_CAssignment: 5438 case SK_StringInit: 5439 case SK_ObjCObjectConversion: 5440 case SK_ArrayInit: 5441 case SK_ParenthesizedArrayInit: 5442 case SK_PassByIndirectCopyRestore: 5443 case SK_PassByIndirectRestore: 5444 case SK_ProduceObjCObject: 5445 case SK_StdInitializerList: 5446 case SK_OCLSamplerInit: 5447 case SK_OCLZeroEvent: { 5448 assert(Args.size() == 1); 5449 CurInit = Args[0]; 5450 if (!CurInit.get()) return ExprError(); 5451 break; 5452 } 5453 5454 case SK_ConstructorInitialization: 5455 case SK_ListConstructorCall: 5456 case SK_ZeroInitialization: 5457 break; 5458 } 5459 5460 // Walk through the computed steps for the initialization sequence, 5461 // performing the specified conversions along the way. 5462 bool ConstructorInitRequiresZeroInit = false; 5463 for (step_iterator Step = step_begin(), StepEnd = step_end(); 5464 Step != StepEnd; ++Step) { 5465 if (CurInit.isInvalid()) 5466 return ExprError(); 5467 5468 QualType SourceType = CurInit.get() ? CurInit.get()->getType() : QualType(); 5469 5470 switch (Step->Kind) { 5471 case SK_ResolveAddressOfOverloadedFunction: 5472 // Overload resolution determined which function invoke; update the 5473 // initializer to reflect that choice. 5474 S.CheckAddressOfMemberAccess(CurInit.get(), Step->Function.FoundDecl); 5475 if (S.DiagnoseUseOfDecl(Step->Function.FoundDecl, Kind.getLocation())) 5476 return ExprError(); 5477 CurInit = S.FixOverloadedFunctionReference(CurInit, 5478 Step->Function.FoundDecl, 5479 Step->Function.Function); 5480 break; 5481 5482 case SK_CastDerivedToBaseRValue: 5483 case SK_CastDerivedToBaseXValue: 5484 case SK_CastDerivedToBaseLValue: { 5485 // We have a derived-to-base cast that produces either an rvalue or an 5486 // lvalue. Perform that cast. 5487 5488 CXXCastPath BasePath; 5489 5490 // Casts to inaccessible base classes are allowed with C-style casts. 5491 bool IgnoreBaseAccess = Kind.isCStyleOrFunctionalCast(); 5492 if (S.CheckDerivedToBaseConversion(SourceType, Step->Type, 5493 CurInit.get()->getLocStart(), 5494 CurInit.get()->getSourceRange(), 5495 &BasePath, IgnoreBaseAccess)) 5496 return ExprError(); 5497 5498 if (S.BasePathInvolvesVirtualBase(BasePath)) { 5499 QualType T = SourceType; 5500 if (const PointerType *Pointer = T->getAs<PointerType>()) 5501 T = Pointer->getPointeeType(); 5502 if (const RecordType *RecordTy = T->getAs<RecordType>()) 5503 S.MarkVTableUsed(CurInit.get()->getLocStart(), 5504 cast<CXXRecordDecl>(RecordTy->getDecl())); 5505 } 5506 5507 ExprValueKind VK = 5508 Step->Kind == SK_CastDerivedToBaseLValue ? 5509 VK_LValue : 5510 (Step->Kind == SK_CastDerivedToBaseXValue ? 5511 VK_XValue : 5512 VK_RValue); 5513 CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, 5514 Step->Type, 5515 CK_DerivedToBase, 5516 CurInit.get(), 5517 &BasePath, VK)); 5518 break; 5519 } 5520 5521 case SK_BindReference: 5522 // References cannot bind to bit-fields (C++ [dcl.init.ref]p5). 5523 if (CurInit.get()->refersToBitField()) { 5524 // We don't necessarily have an unambiguous source bit-field. 5525 FieldDecl *BitField = CurInit.get()->getSourceBitField(); 5526 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield) 5527 << Entity.getType().isVolatileQualified() 5528 << (BitField ? BitField->getDeclName() : DeclarationName()) 5529 << (BitField != NULL) 5530 << CurInit.get()->getSourceRange(); 5531 if (BitField) 5532 S.Diag(BitField->getLocation(), diag::note_bitfield_decl); 5533 5534 return ExprError(); 5535 } 5536 5537 if (CurInit.get()->refersToVectorElement()) { 5538 // References cannot bind to vector elements. 5539 S.Diag(Kind.getLocation(), diag::err_reference_bind_to_vector_element) 5540 << Entity.getType().isVolatileQualified() 5541 << CurInit.get()->getSourceRange(); 5542 PrintInitLocationNote(S, Entity); 5543 return ExprError(); 5544 } 5545 5546 // Reference binding does not have any corresponding ASTs. 5547 5548 // Check exception specifications 5549 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType)) 5550 return ExprError(); 5551 5552 break; 5553 5554 case SK_BindReferenceToTemporary: { 5555 // Make sure the "temporary" is actually an rvalue. 5556 assert(CurInit.get()->isRValue() && "not a temporary"); 5557 5558 // Check exception specifications 5559 if (S.CheckExceptionSpecCompatibility(CurInit.get(), DestType)) 5560 return ExprError(); 5561 5562 // Maybe lifetime-extend the temporary's subobjects to match the 5563 // entity's lifetime. 5564 const ValueDecl *ExtendingDecl = 5565 getDeclForTemporaryLifetimeExtension(Entity); 5566 if (ExtendingDecl) 5567 performLifetimeExtension(CurInit.get(), ExtendingDecl); 5568 5569 // Materialize the temporary into memory. 5570 CurInit = new (S.Context) MaterializeTemporaryExpr( 5571 Entity.getType().getNonReferenceType(), CurInit.get(), 5572 Entity.getType()->isLValueReferenceType(), ExtendingDecl); 5573 5574 // If we're binding to an Objective-C object that has lifetime, we 5575 // need cleanups. 5576 if (S.getLangOpts().ObjCAutoRefCount && 5577 CurInit.get()->getType()->isObjCLifetimeType()) 5578 S.ExprNeedsCleanups = true; 5579 5580 break; 5581 } 5582 5583 case SK_ExtraneousCopyToTemporary: 5584 CurInit = CopyObject(S, Step->Type, Entity, CurInit, 5585 /*IsExtraneousCopy=*/true); 5586 break; 5587 5588 case SK_UserConversion: { 5589 // We have a user-defined conversion that invokes either a constructor 5590 // or a conversion function. 5591 CastKind CastKind; 5592 bool IsCopy = false; 5593 FunctionDecl *Fn = Step->Function.Function; 5594 DeclAccessPair FoundFn = Step->Function.FoundDecl; 5595 bool HadMultipleCandidates = Step->Function.HadMultipleCandidates; 5596 bool CreatedObject = false; 5597 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) { 5598 // Build a call to the selected constructor. 5599 SmallVector<Expr*, 8> ConstructorArgs; 5600 SourceLocation Loc = CurInit.get()->getLocStart(); 5601 CurInit.release(); // Ownership transferred into MultiExprArg, below. 5602 5603 // Determine the arguments required to actually perform the constructor 5604 // call. 5605 Expr *Arg = CurInit.get(); 5606 if (S.CompleteConstructorCall(Constructor, 5607 MultiExprArg(&Arg, 1), 5608 Loc, ConstructorArgs)) 5609 return ExprError(); 5610 5611 // Build an expression that constructs a temporary. 5612 CurInit = S.BuildCXXConstructExpr(Loc, Step->Type, Constructor, 5613 ConstructorArgs, 5614 HadMultipleCandidates, 5615 /*ListInit*/ false, 5616 /*ZeroInit*/ false, 5617 CXXConstructExpr::CK_Complete, 5618 SourceRange()); 5619 if (CurInit.isInvalid()) 5620 return ExprError(); 5621 5622 S.CheckConstructorAccess(Kind.getLocation(), Constructor, Entity, 5623 FoundFn.getAccess()); 5624 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation())) 5625 return ExprError(); 5626 5627 CastKind = CK_ConstructorConversion; 5628 QualType Class = S.Context.getTypeDeclType(Constructor->getParent()); 5629 if (S.Context.hasSameUnqualifiedType(SourceType, Class) || 5630 S.IsDerivedFrom(SourceType, Class)) 5631 IsCopy = true; 5632 5633 CreatedObject = true; 5634 } else { 5635 // Build a call to the conversion function. 5636 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(Fn); 5637 S.CheckMemberOperatorAccess(Kind.getLocation(), CurInit.get(), 0, 5638 FoundFn); 5639 if (S.DiagnoseUseOfDecl(FoundFn, Kind.getLocation())) 5640 return ExprError(); 5641 5642 // FIXME: Should we move this initialization into a separate 5643 // derived-to-base conversion? I believe the answer is "no", because 5644 // we don't want to turn off access control here for c-style casts. 5645 ExprResult CurInitExprRes = 5646 S.PerformObjectArgumentInitialization(CurInit.take(), /*Qualifier=*/0, 5647 FoundFn, Conversion); 5648 if(CurInitExprRes.isInvalid()) 5649 return ExprError(); 5650 CurInit = CurInitExprRes; 5651 5652 // Build the actual call to the conversion function. 5653 CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion, 5654 HadMultipleCandidates); 5655 if (CurInit.isInvalid() || !CurInit.get()) 5656 return ExprError(); 5657 5658 CastKind = CK_UserDefinedConversion; 5659 5660 CreatedObject = Conversion->getResultType()->isRecordType(); 5661 } 5662 5663 bool RequiresCopy = !IsCopy && !isReferenceBinding(Steps.back()); 5664 bool MaybeBindToTemp = RequiresCopy || shouldBindAsTemporary(Entity); 5665 5666 if (!MaybeBindToTemp && CreatedObject && shouldDestroyTemporary(Entity)) { 5667 QualType T = CurInit.get()->getType(); 5668 if (const RecordType *Record = T->getAs<RecordType>()) { 5669 CXXDestructorDecl *Destructor 5670 = S.LookupDestructor(cast<CXXRecordDecl>(Record->getDecl())); 5671 S.CheckDestructorAccess(CurInit.get()->getLocStart(), Destructor, 5672 S.PDiag(diag::err_access_dtor_temp) << T); 5673 S.MarkFunctionReferenced(CurInit.get()->getLocStart(), Destructor); 5674 if (S.DiagnoseUseOfDecl(Destructor, CurInit.get()->getLocStart())) 5675 return ExprError(); 5676 } 5677 } 5678 5679 CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, 5680 CurInit.get()->getType(), 5681 CastKind, CurInit.get(), 0, 5682 CurInit.get()->getValueKind())); 5683 if (MaybeBindToTemp) 5684 CurInit = S.MaybeBindToTemporary(CurInit.takeAs<Expr>()); 5685 if (RequiresCopy) 5686 CurInit = CopyObject(S, Entity.getType().getNonReferenceType(), Entity, 5687 CurInit, /*IsExtraneousCopy=*/false); 5688 break; 5689 } 5690 5691 case SK_QualificationConversionLValue: 5692 case SK_QualificationConversionXValue: 5693 case SK_QualificationConversionRValue: { 5694 // Perform a qualification conversion; these can never go wrong. 5695 ExprValueKind VK = 5696 Step->Kind == SK_QualificationConversionLValue ? 5697 VK_LValue : 5698 (Step->Kind == SK_QualificationConversionXValue ? 5699 VK_XValue : 5700 VK_RValue); 5701 CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type, CK_NoOp, VK); 5702 break; 5703 } 5704 5705 case SK_LValueToRValue: { 5706 assert(CurInit.get()->isGLValue() && "cannot load from a prvalue"); 5707 CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, Step->Type, 5708 CK_LValueToRValue, 5709 CurInit.take(), 5710 /*BasePath=*/0, 5711 VK_RValue)); 5712 break; 5713 } 5714 5715 case SK_ConversionSequence: { 5716 Sema::CheckedConversionKind CCK 5717 = Kind.isCStyleCast()? Sema::CCK_CStyleCast 5718 : Kind.isFunctionalCast()? Sema::CCK_FunctionalCast 5719 : Kind.isExplicitCast()? Sema::CCK_OtherCast 5720 : Sema::CCK_ImplicitConversion; 5721 ExprResult CurInitExprRes = 5722 S.PerformImplicitConversion(CurInit.get(), Step->Type, *Step->ICS, 5723 getAssignmentAction(Entity), CCK); 5724 if (CurInitExprRes.isInvalid()) 5725 return ExprError(); 5726 CurInit = CurInitExprRes; 5727 break; 5728 } 5729 5730 case SK_ListInitialization: { 5731 InitListExpr *InitList = cast<InitListExpr>(CurInit.get()); 5732 // Hack: We must pass *ResultType if available in order to set the type 5733 // of arrays, e.g. in 'int ar[] = {1, 2, 3};'. 5734 // But in 'const X &x = {1, 2, 3};' we're supposed to initialize a 5735 // temporary, not a reference, so we should pass Ty. 5736 // Worst case: 'const int (&arref)[] = {1, 2, 3};'. 5737 // Since this step is never used for a reference directly, we explicitly 5738 // unwrap references here and rewrap them afterwards. 5739 // We also need to create a InitializeTemporary entity for this. 5740 QualType Ty = ResultType ? ResultType->getNonReferenceType() : Step->Type; 5741 bool IsTemporary = Entity.getType()->isReferenceType(); 5742 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary(Ty); 5743 InitializedEntity InitEntity = IsTemporary ? TempEntity : Entity; 5744 InitListChecker PerformInitList(S, InitEntity, 5745 InitList, Ty, /*VerifyOnly=*/false); 5746 if (PerformInitList.HadError()) 5747 return ExprError(); 5748 5749 if (ResultType) { 5750 if ((*ResultType)->isRValueReferenceType()) 5751 Ty = S.Context.getRValueReferenceType(Ty); 5752 else if ((*ResultType)->isLValueReferenceType()) 5753 Ty = S.Context.getLValueReferenceType(Ty, 5754 (*ResultType)->getAs<LValueReferenceType>()->isSpelledAsLValue()); 5755 *ResultType = Ty; 5756 } 5757 5758 InitListExpr *StructuredInitList = 5759 PerformInitList.getFullyStructuredList(); 5760 CurInit.release(); 5761 CurInit = shouldBindAsTemporary(InitEntity) 5762 ? S.MaybeBindToTemporary(StructuredInitList) 5763 : S.Owned(StructuredInitList); 5764 break; 5765 } 5766 5767 case SK_ListConstructorCall: { 5768 // When an initializer list is passed for a parameter of type "reference 5769 // to object", we don't get an EK_Temporary entity, but instead an 5770 // EK_Parameter entity with reference type. 5771 // FIXME: This is a hack. What we really should do is create a user 5772 // conversion step for this case, but this makes it considerably more 5773 // complicated. For now, this will do. 5774 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary( 5775 Entity.getType().getNonReferenceType()); 5776 bool UseTemporary = Entity.getType()->isReferenceType(); 5777 assert(Args.size() == 1 && "expected a single argument for list init"); 5778 InitListExpr *InitList = cast<InitListExpr>(Args[0]); 5779 S.Diag(InitList->getExprLoc(), diag::warn_cxx98_compat_ctor_list_init) 5780 << InitList->getSourceRange(); 5781 MultiExprArg Arg(InitList->getInits(), InitList->getNumInits()); 5782 CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity : 5783 Entity, 5784 Kind, Arg, *Step, 5785 ConstructorInitRequiresZeroInit, 5786 /*IsListInitialization*/ true); 5787 break; 5788 } 5789 5790 case SK_UnwrapInitList: 5791 CurInit = S.Owned(cast<InitListExpr>(CurInit.take())->getInit(0)); 5792 break; 5793 5794 case SK_RewrapInitList: { 5795 Expr *E = CurInit.take(); 5796 InitListExpr *Syntactic = Step->WrappingSyntacticList; 5797 InitListExpr *ILE = new (S.Context) InitListExpr(S.Context, 5798 Syntactic->getLBraceLoc(), E, Syntactic->getRBraceLoc()); 5799 ILE->setSyntacticForm(Syntactic); 5800 ILE->setType(E->getType()); 5801 ILE->setValueKind(E->getValueKind()); 5802 CurInit = S.Owned(ILE); 5803 break; 5804 } 5805 5806 case SK_ConstructorInitialization: { 5807 // When an initializer list is passed for a parameter of type "reference 5808 // to object", we don't get an EK_Temporary entity, but instead an 5809 // EK_Parameter entity with reference type. 5810 // FIXME: This is a hack. What we really should do is create a user 5811 // conversion step for this case, but this makes it considerably more 5812 // complicated. For now, this will do. 5813 InitializedEntity TempEntity = InitializedEntity::InitializeTemporary( 5814 Entity.getType().getNonReferenceType()); 5815 bool UseTemporary = Entity.getType()->isReferenceType(); 5816 CurInit = PerformConstructorInitialization(S, UseTemporary ? TempEntity 5817 : Entity, 5818 Kind, Args, *Step, 5819 ConstructorInitRequiresZeroInit, 5820 /*IsListInitialization*/ false); 5821 break; 5822 } 5823 5824 case SK_ZeroInitialization: { 5825 step_iterator NextStep = Step; 5826 ++NextStep; 5827 if (NextStep != StepEnd && 5828 (NextStep->Kind == SK_ConstructorInitialization || 5829 NextStep->Kind == SK_ListConstructorCall)) { 5830 // The need for zero-initialization is recorded directly into 5831 // the call to the object's constructor within the next step. 5832 ConstructorInitRequiresZeroInit = true; 5833 } else if (Kind.getKind() == InitializationKind::IK_Value && 5834 S.getLangOpts().CPlusPlus && 5835 !Kind.isImplicitValueInit()) { 5836 TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo(); 5837 if (!TSInfo) 5838 TSInfo = S.Context.getTrivialTypeSourceInfo(Step->Type, 5839 Kind.getRange().getBegin()); 5840 5841 CurInit = S.Owned(new (S.Context) CXXScalarValueInitExpr( 5842 TSInfo->getType().getNonLValueExprType(S.Context), 5843 TSInfo, 5844 Kind.getRange().getEnd())); 5845 } else { 5846 CurInit = S.Owned(new (S.Context) ImplicitValueInitExpr(Step->Type)); 5847 } 5848 break; 5849 } 5850 5851 case SK_CAssignment: { 5852 QualType SourceType = CurInit.get()->getType(); 5853 ExprResult Result = CurInit; 5854 Sema::AssignConvertType ConvTy = 5855 S.CheckSingleAssignmentConstraints(Step->Type, Result); 5856 if (Result.isInvalid()) 5857 return ExprError(); 5858 CurInit = Result; 5859 5860 // If this is a call, allow conversion to a transparent union. 5861 ExprResult CurInitExprRes = CurInit; 5862 if (ConvTy != Sema::Compatible && 5863 Entity.getKind() == InitializedEntity::EK_Parameter && 5864 S.CheckTransparentUnionArgumentConstraints(Step->Type, CurInitExprRes) 5865 == Sema::Compatible) 5866 ConvTy = Sema::Compatible; 5867 if (CurInitExprRes.isInvalid()) 5868 return ExprError(); 5869 CurInit = CurInitExprRes; 5870 5871 bool Complained; 5872 if (S.DiagnoseAssignmentResult(ConvTy, Kind.getLocation(), 5873 Step->Type, SourceType, 5874 CurInit.get(), 5875 getAssignmentAction(Entity), 5876 &Complained)) { 5877 PrintInitLocationNote(S, Entity); 5878 return ExprError(); 5879 } else if (Complained) 5880 PrintInitLocationNote(S, Entity); 5881 break; 5882 } 5883 5884 case SK_StringInit: { 5885 QualType Ty = Step->Type; 5886 CheckStringInit(CurInit.get(), ResultType ? *ResultType : Ty, 5887 S.Context.getAsArrayType(Ty), S); 5888 break; 5889 } 5890 5891 case SK_ObjCObjectConversion: 5892 CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type, 5893 CK_ObjCObjectLValueCast, 5894 CurInit.get()->getValueKind()); 5895 break; 5896 5897 case SK_ArrayInit: 5898 // Okay: we checked everything before creating this step. Note that 5899 // this is a GNU extension. 5900 S.Diag(Kind.getLocation(), diag::ext_array_init_copy) 5901 << Step->Type << CurInit.get()->getType() 5902 << CurInit.get()->getSourceRange(); 5903 5904 // If the destination type is an incomplete array type, update the 5905 // type accordingly. 5906 if (ResultType) { 5907 if (const IncompleteArrayType *IncompleteDest 5908 = S.Context.getAsIncompleteArrayType(Step->Type)) { 5909 if (const ConstantArrayType *ConstantSource 5910 = S.Context.getAsConstantArrayType(CurInit.get()->getType())) { 5911 *ResultType = S.Context.getConstantArrayType( 5912 IncompleteDest->getElementType(), 5913 ConstantSource->getSize(), 5914 ArrayType::Normal, 0); 5915 } 5916 } 5917 } 5918 break; 5919 5920 case SK_ParenthesizedArrayInit: 5921 // Okay: we checked everything before creating this step. Note that 5922 // this is a GNU extension. 5923 S.Diag(Kind.getLocation(), diag::ext_array_init_parens) 5924 << CurInit.get()->getSourceRange(); 5925 break; 5926 5927 case SK_PassByIndirectCopyRestore: 5928 case SK_PassByIndirectRestore: 5929 checkIndirectCopyRestoreSource(S, CurInit.get()); 5930 CurInit = S.Owned(new (S.Context) 5931 ObjCIndirectCopyRestoreExpr(CurInit.take(), Step->Type, 5932 Step->Kind == SK_PassByIndirectCopyRestore)); 5933 break; 5934 5935 case SK_ProduceObjCObject: 5936 CurInit = S.Owned(ImplicitCastExpr::Create(S.Context, Step->Type, 5937 CK_ARCProduceObject, 5938 CurInit.take(), 0, VK_RValue)); 5939 break; 5940 5941 case SK_StdInitializerList: { 5942 QualType Dest = Step->Type; 5943 QualType E; 5944 bool Success = S.isStdInitializerList(Dest.getNonReferenceType(), &E); 5945 (void)Success; 5946 assert(Success && "Destination type changed?"); 5947 5948 // If the element type has a destructor, check it. 5949 if (CXXRecordDecl *RD = E->getAsCXXRecordDecl()) { 5950 if (!RD->hasIrrelevantDestructor()) { 5951 if (CXXDestructorDecl *Destructor = S.LookupDestructor(RD)) { 5952 S.MarkFunctionReferenced(Kind.getLocation(), Destructor); 5953 S.CheckDestructorAccess(Kind.getLocation(), Destructor, 5954 S.PDiag(diag::err_access_dtor_temp) << E); 5955 if (S.DiagnoseUseOfDecl(Destructor, Kind.getLocation())) 5956 return ExprError(); 5957 } 5958 } 5959 } 5960 5961 InitListExpr *ILE = cast<InitListExpr>(CurInit.take()); 5962 S.Diag(ILE->getExprLoc(), diag::warn_cxx98_compat_initializer_list_init) 5963 << ILE->getSourceRange(); 5964 unsigned NumInits = ILE->getNumInits(); 5965 SmallVector<Expr*, 16> Converted(NumInits); 5966 InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( 5967 S.Context.getConstantArrayType(E, 5968 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), 5969 NumInits), 5970 ArrayType::Normal, 0)); 5971 InitializedEntity Element =InitializedEntity::InitializeElement(S.Context, 5972 0, HiddenArray); 5973 for (unsigned i = 0; i < NumInits; ++i) { 5974 Element.setElementIndex(i); 5975 ExprResult Init = S.Owned(ILE->getInit(i)); 5976 ExprResult Res = S.PerformCopyInitialization( 5977 Element, Init.get()->getExprLoc(), Init, 5978 /*TopLevelOfInitList=*/ true); 5979 if (Res.isInvalid()) 5980 return ExprError(); 5981 Converted[i] = Res.take(); 5982 } 5983 InitListExpr *Semantic = new (S.Context) 5984 InitListExpr(S.Context, ILE->getLBraceLoc(), 5985 Converted, ILE->getRBraceLoc()); 5986 Semantic->setSyntacticForm(ILE); 5987 Semantic->setType(Dest); 5988 Semantic->setInitializesStdInitializerList(); 5989 CurInit = S.Owned(Semantic); 5990 break; 5991 } 5992 case SK_OCLSamplerInit: { 5993 assert(Step->Type->isSamplerT() && 5994 "Sampler initialization on non sampler type."); 5995 5996 QualType SourceType = CurInit.get()->getType(); 5997 InitializedEntity::EntityKind EntityKind = Entity.getKind(); 5998 5999 if (EntityKind == InitializedEntity::EK_Parameter) { 6000 if (!SourceType->isSamplerT()) 6001 S.Diag(Kind.getLocation(), diag::err_sampler_argument_required) 6002 << SourceType; 6003 } else if (EntityKind != InitializedEntity::EK_Variable) { 6004 llvm_unreachable("Invalid EntityKind!"); 6005 } 6006 6007 break; 6008 } 6009 case SK_OCLZeroEvent: { 6010 assert(Step->Type->isEventT() && 6011 "Event initialization on non event type."); 6012 6013 CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type, 6014 CK_ZeroToOCLEvent, 6015 CurInit.get()->getValueKind()); 6016 break; 6017 } 6018 } 6019 } 6020 6021 // Diagnose non-fatal problems with the completed initialization. 6022 if (Entity.getKind() == InitializedEntity::EK_Member && 6023 cast<FieldDecl>(Entity.getDecl())->isBitField()) 6024 S.CheckBitFieldInitialization(Kind.getLocation(), 6025 cast<FieldDecl>(Entity.getDecl()), 6026 CurInit.get()); 6027 6028 return CurInit; 6029} 6030 6031/// Somewhere within T there is an uninitialized reference subobject. 6032/// Dig it out and diagnose it. 6033static bool DiagnoseUninitializedReference(Sema &S, SourceLocation Loc, 6034 QualType T) { 6035 if (T->isReferenceType()) { 6036 S.Diag(Loc, diag::err_reference_without_init) 6037 << T.getNonReferenceType(); 6038 return true; 6039 } 6040 6041 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); 6042 if (!RD || !RD->hasUninitializedReferenceMember()) 6043 return false; 6044 6045 for (CXXRecordDecl::field_iterator FI = RD->field_begin(), 6046 FE = RD->field_end(); FI != FE; ++FI) { 6047 if (FI->isUnnamedBitfield()) 6048 continue; 6049 6050 if (DiagnoseUninitializedReference(S, FI->getLocation(), FI->getType())) { 6051 S.Diag(Loc, diag::note_value_initialization_here) << RD; 6052 return true; 6053 } 6054 } 6055 6056 for (CXXRecordDecl::base_class_iterator BI = RD->bases_begin(), 6057 BE = RD->bases_end(); 6058 BI != BE; ++BI) { 6059 if (DiagnoseUninitializedReference(S, BI->getLocStart(), BI->getType())) { 6060 S.Diag(Loc, diag::note_value_initialization_here) << RD; 6061 return true; 6062 } 6063 } 6064 6065 return false; 6066} 6067 6068 6069//===----------------------------------------------------------------------===// 6070// Diagnose initialization failures 6071//===----------------------------------------------------------------------===// 6072 6073/// Emit notes associated with an initialization that failed due to a 6074/// "simple" conversion failure. 6075static void emitBadConversionNotes(Sema &S, const InitializedEntity &entity, 6076 Expr *op) { 6077 QualType destType = entity.getType(); 6078 if (destType.getNonReferenceType()->isObjCObjectPointerType() && 6079 op->getType()->isObjCObjectPointerType()) { 6080 6081 // Emit a possible note about the conversion failing because the 6082 // operand is a message send with a related result type. 6083 S.EmitRelatedResultTypeNote(op); 6084 6085 // Emit a possible note about a return failing because we're 6086 // expecting a related result type. 6087 if (entity.getKind() == InitializedEntity::EK_Result) 6088 S.EmitRelatedResultTypeNoteForReturn(destType); 6089 } 6090} 6091 6092bool InitializationSequence::Diagnose(Sema &S, 6093 const InitializedEntity &Entity, 6094 const InitializationKind &Kind, 6095 ArrayRef<Expr *> Args) { 6096 if (!Failed()) 6097 return false; 6098 6099 QualType DestType = Entity.getType(); 6100 switch (Failure) { 6101 case FK_TooManyInitsForReference: 6102 // FIXME: Customize for the initialized entity? 6103 if (Args.empty()) { 6104 // Dig out the reference subobject which is uninitialized and diagnose it. 6105 // If this is value-initialization, this could be nested some way within 6106 // the target type. 6107 assert(Kind.getKind() == InitializationKind::IK_Value || 6108 DestType->isReferenceType()); 6109 bool Diagnosed = 6110 DiagnoseUninitializedReference(S, Kind.getLocation(), DestType); 6111 assert(Diagnosed && "couldn't find uninitialized reference to diagnose"); 6112 (void)Diagnosed; 6113 } else // FIXME: diagnostic below could be better! 6114 S.Diag(Kind.getLocation(), diag::err_reference_has_multiple_inits) 6115 << SourceRange(Args.front()->getLocStart(), Args.back()->getLocEnd()); 6116 break; 6117 6118 case FK_ArrayNeedsInitList: 6119 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 0; 6120 break; 6121 case FK_ArrayNeedsInitListOrStringLiteral: 6122 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 1; 6123 break; 6124 case FK_ArrayNeedsInitListOrWideStringLiteral: 6125 S.Diag(Kind.getLocation(), diag::err_array_init_not_init_list) << 2; 6126 break; 6127 case FK_NarrowStringIntoWideCharArray: 6128 S.Diag(Kind.getLocation(), diag::err_array_init_narrow_string_into_wchar); 6129 break; 6130 case FK_WideStringIntoCharArray: 6131 S.Diag(Kind.getLocation(), diag::err_array_init_wide_string_into_char); 6132 break; 6133 case FK_IncompatWideStringIntoWideChar: 6134 S.Diag(Kind.getLocation(), 6135 diag::err_array_init_incompat_wide_string_into_wchar); 6136 break; 6137 case FK_ArrayTypeMismatch: 6138 case FK_NonConstantArrayInit: 6139 S.Diag(Kind.getLocation(), 6140 (Failure == FK_ArrayTypeMismatch 6141 ? diag::err_array_init_different_type 6142 : diag::err_array_init_non_constant_array)) 6143 << DestType.getNonReferenceType() 6144 << Args[0]->getType() 6145 << Args[0]->getSourceRange(); 6146 break; 6147 6148 case FK_VariableLengthArrayHasInitializer: 6149 S.Diag(Kind.getLocation(), diag::err_variable_object_no_init) 6150 << Args[0]->getSourceRange(); 6151 break; 6152 6153 case FK_AddressOfOverloadFailed: { 6154 DeclAccessPair Found; 6155 S.ResolveAddressOfOverloadedFunction(Args[0], 6156 DestType.getNonReferenceType(), 6157 true, 6158 Found); 6159 break; 6160 } 6161 6162 case FK_ReferenceInitOverloadFailed: 6163 case FK_UserConversionOverloadFailed: 6164 switch (FailedOverloadResult) { 6165 case OR_Ambiguous: 6166 if (Failure == FK_UserConversionOverloadFailed) 6167 S.Diag(Kind.getLocation(), diag::err_typecheck_ambiguous_condition) 6168 << Args[0]->getType() << DestType 6169 << Args[0]->getSourceRange(); 6170 else 6171 S.Diag(Kind.getLocation(), diag::err_ref_init_ambiguous) 6172 << DestType << Args[0]->getType() 6173 << Args[0]->getSourceRange(); 6174 6175 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args); 6176 break; 6177 6178 case OR_No_Viable_Function: 6179 S.Diag(Kind.getLocation(), diag::err_typecheck_nonviable_condition) 6180 << Args[0]->getType() << DestType.getNonReferenceType() 6181 << Args[0]->getSourceRange(); 6182 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args); 6183 break; 6184 6185 case OR_Deleted: { 6186 S.Diag(Kind.getLocation(), diag::err_typecheck_deleted_function) 6187 << Args[0]->getType() << DestType.getNonReferenceType() 6188 << Args[0]->getSourceRange(); 6189 OverloadCandidateSet::iterator Best; 6190 OverloadingResult Ovl 6191 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best, 6192 true); 6193 if (Ovl == OR_Deleted) { 6194 S.NoteDeletedFunction(Best->Function); 6195 } else { 6196 llvm_unreachable("Inconsistent overload resolution?"); 6197 } 6198 break; 6199 } 6200 6201 case OR_Success: 6202 llvm_unreachable("Conversion did not fail!"); 6203 } 6204 break; 6205 6206 case FK_NonConstLValueReferenceBindingToTemporary: 6207 if (isa<InitListExpr>(Args[0])) { 6208 S.Diag(Kind.getLocation(), 6209 diag::err_lvalue_reference_bind_to_initlist) 6210 << DestType.getNonReferenceType().isVolatileQualified() 6211 << DestType.getNonReferenceType() 6212 << Args[0]->getSourceRange(); 6213 break; 6214 } 6215 // Intentional fallthrough 6216 6217 case FK_NonConstLValueReferenceBindingToUnrelated: 6218 S.Diag(Kind.getLocation(), 6219 Failure == FK_NonConstLValueReferenceBindingToTemporary 6220 ? diag::err_lvalue_reference_bind_to_temporary 6221 : diag::err_lvalue_reference_bind_to_unrelated) 6222 << DestType.getNonReferenceType().isVolatileQualified() 6223 << DestType.getNonReferenceType() 6224 << Args[0]->getType() 6225 << Args[0]->getSourceRange(); 6226 break; 6227 6228 case FK_RValueReferenceBindingToLValue: 6229 S.Diag(Kind.getLocation(), diag::err_lvalue_to_rvalue_ref) 6230 << DestType.getNonReferenceType() << Args[0]->getType() 6231 << Args[0]->getSourceRange(); 6232 break; 6233 6234 case FK_ReferenceInitDropsQualifiers: 6235 S.Diag(Kind.getLocation(), diag::err_reference_bind_drops_quals) 6236 << DestType.getNonReferenceType() 6237 << Args[0]->getType() 6238 << Args[0]->getSourceRange(); 6239 break; 6240 6241 case FK_ReferenceInitFailed: 6242 S.Diag(Kind.getLocation(), diag::err_reference_bind_failed) 6243 << DestType.getNonReferenceType() 6244 << Args[0]->isLValue() 6245 << Args[0]->getType() 6246 << Args[0]->getSourceRange(); 6247 emitBadConversionNotes(S, Entity, Args[0]); 6248 break; 6249 6250 case FK_ConversionFailed: { 6251 QualType FromType = Args[0]->getType(); 6252 PartialDiagnostic PDiag = S.PDiag(diag::err_init_conversion_failed) 6253 << (int)Entity.getKind() 6254 << DestType 6255 << Args[0]->isLValue() 6256 << FromType 6257 << Args[0]->getSourceRange(); 6258 S.HandleFunctionTypeMismatch(PDiag, FromType, DestType); 6259 S.Diag(Kind.getLocation(), PDiag); 6260 emitBadConversionNotes(S, Entity, Args[0]); 6261 break; 6262 } 6263 6264 case FK_ConversionFromPropertyFailed: 6265 // No-op. This error has already been reported. 6266 break; 6267 6268 case FK_TooManyInitsForScalar: { 6269 SourceRange R; 6270 6271 if (InitListExpr *InitList = dyn_cast<InitListExpr>(Args[0])) 6272 R = SourceRange(InitList->getInit(0)->getLocEnd(), 6273 InitList->getLocEnd()); 6274 else 6275 R = SourceRange(Args.front()->getLocEnd(), Args.back()->getLocEnd()); 6276 6277 R.setBegin(S.PP.getLocForEndOfToken(R.getBegin())); 6278 if (Kind.isCStyleOrFunctionalCast()) 6279 S.Diag(Kind.getLocation(), diag::err_builtin_func_cast_more_than_one_arg) 6280 << R; 6281 else 6282 S.Diag(Kind.getLocation(), diag::err_excess_initializers) 6283 << /*scalar=*/2 << R; 6284 break; 6285 } 6286 6287 case FK_ReferenceBindingToInitList: 6288 S.Diag(Kind.getLocation(), diag::err_reference_bind_init_list) 6289 << DestType.getNonReferenceType() << Args[0]->getSourceRange(); 6290 break; 6291 6292 case FK_InitListBadDestinationType: 6293 S.Diag(Kind.getLocation(), diag::err_init_list_bad_dest_type) 6294 << (DestType->isRecordType()) << DestType << Args[0]->getSourceRange(); 6295 break; 6296 6297 case FK_ListConstructorOverloadFailed: 6298 case FK_ConstructorOverloadFailed: { 6299 SourceRange ArgsRange; 6300 if (Args.size()) 6301 ArgsRange = SourceRange(Args.front()->getLocStart(), 6302 Args.back()->getLocEnd()); 6303 6304 if (Failure == FK_ListConstructorOverloadFailed) { 6305 assert(Args.size() == 1 && "List construction from other than 1 argument."); 6306 InitListExpr *InitList = cast<InitListExpr>(Args[0]); 6307 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits()); 6308 } 6309 6310 // FIXME: Using "DestType" for the entity we're printing is probably 6311 // bad. 6312 switch (FailedOverloadResult) { 6313 case OR_Ambiguous: 6314 S.Diag(Kind.getLocation(), diag::err_ovl_ambiguous_init) 6315 << DestType << ArgsRange; 6316 FailedCandidateSet.NoteCandidates(S, OCD_ViableCandidates, Args); 6317 break; 6318 6319 case OR_No_Viable_Function: 6320 if (Kind.getKind() == InitializationKind::IK_Default && 6321 (Entity.getKind() == InitializedEntity::EK_Base || 6322 Entity.getKind() == InitializedEntity::EK_Member) && 6323 isa<CXXConstructorDecl>(S.CurContext)) { 6324 // This is implicit default initialization of a member or 6325 // base within a constructor. If no viable function was 6326 // found, notify the user that she needs to explicitly 6327 // initialize this base/member. 6328 CXXConstructorDecl *Constructor 6329 = cast<CXXConstructorDecl>(S.CurContext); 6330 if (Entity.getKind() == InitializedEntity::EK_Base) { 6331 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 6332 << (Constructor->getInheritedConstructor() ? 2 : 6333 Constructor->isImplicit() ? 1 : 0) 6334 << S.Context.getTypeDeclType(Constructor->getParent()) 6335 << /*base=*/0 6336 << Entity.getType(); 6337 6338 RecordDecl *BaseDecl 6339 = Entity.getBaseSpecifier()->getType()->getAs<RecordType>() 6340 ->getDecl(); 6341 S.Diag(BaseDecl->getLocation(), diag::note_previous_decl) 6342 << S.Context.getTagDeclType(BaseDecl); 6343 } else { 6344 S.Diag(Kind.getLocation(), diag::err_missing_default_ctor) 6345 << (Constructor->getInheritedConstructor() ? 2 : 6346 Constructor->isImplicit() ? 1 : 0) 6347 << S.Context.getTypeDeclType(Constructor->getParent()) 6348 << /*member=*/1 6349 << Entity.getName(); 6350 S.Diag(Entity.getDecl()->getLocation(), diag::note_field_decl); 6351 6352 if (const RecordType *Record 6353 = Entity.getType()->getAs<RecordType>()) 6354 S.Diag(Record->getDecl()->getLocation(), 6355 diag::note_previous_decl) 6356 << S.Context.getTagDeclType(Record->getDecl()); 6357 } 6358 break; 6359 } 6360 6361 S.Diag(Kind.getLocation(), diag::err_ovl_no_viable_function_in_init) 6362 << DestType << ArgsRange; 6363 FailedCandidateSet.NoteCandidates(S, OCD_AllCandidates, Args); 6364 break; 6365 6366 case OR_Deleted: { 6367 OverloadCandidateSet::iterator Best; 6368 OverloadingResult Ovl 6369 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best); 6370 if (Ovl != OR_Deleted) { 6371 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) 6372 << true << DestType << ArgsRange; 6373 llvm_unreachable("Inconsistent overload resolution?"); 6374 break; 6375 } 6376 6377 // If this is a defaulted or implicitly-declared function, then 6378 // it was implicitly deleted. Make it clear that the deletion was 6379 // implicit. 6380 if (S.isImplicitlyDeleted(Best->Function)) 6381 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_special_init) 6382 << S.getSpecialMember(cast<CXXMethodDecl>(Best->Function)) 6383 << DestType << ArgsRange; 6384 else 6385 S.Diag(Kind.getLocation(), diag::err_ovl_deleted_init) 6386 << true << DestType << ArgsRange; 6387 6388 S.NoteDeletedFunction(Best->Function); 6389 break; 6390 } 6391 6392 case OR_Success: 6393 llvm_unreachable("Conversion did not fail!"); 6394 } 6395 } 6396 break; 6397 6398 case FK_DefaultInitOfConst: 6399 if (Entity.getKind() == InitializedEntity::EK_Member && 6400 isa<CXXConstructorDecl>(S.CurContext)) { 6401 // This is implicit default-initialization of a const member in 6402 // a constructor. Complain that it needs to be explicitly 6403 // initialized. 6404 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(S.CurContext); 6405 S.Diag(Kind.getLocation(), diag::err_uninitialized_member_in_ctor) 6406 << (Constructor->getInheritedConstructor() ? 2 : 6407 Constructor->isImplicit() ? 1 : 0) 6408 << S.Context.getTypeDeclType(Constructor->getParent()) 6409 << /*const=*/1 6410 << Entity.getName(); 6411 S.Diag(Entity.getDecl()->getLocation(), diag::note_previous_decl) 6412 << Entity.getName(); 6413 } else { 6414 S.Diag(Kind.getLocation(), diag::err_default_init_const) 6415 << DestType << (bool)DestType->getAs<RecordType>(); 6416 } 6417 break; 6418 6419 case FK_Incomplete: 6420 S.RequireCompleteType(Kind.getLocation(), FailedIncompleteType, 6421 diag::err_init_incomplete_type); 6422 break; 6423 6424 case FK_ListInitializationFailed: { 6425 // Run the init list checker again to emit diagnostics. 6426 InitListExpr* InitList = cast<InitListExpr>(Args[0]); 6427 QualType DestType = Entity.getType(); 6428 InitListChecker DiagnoseInitList(S, Entity, InitList, 6429 DestType, /*VerifyOnly=*/false); 6430 assert(DiagnoseInitList.HadError() && 6431 "Inconsistent init list check result."); 6432 break; 6433 } 6434 6435 case FK_PlaceholderType: { 6436 // FIXME: Already diagnosed! 6437 break; 6438 } 6439 6440 case FK_InitListElementCopyFailure: { 6441 // Try to perform all copies again. 6442 InitListExpr* InitList = cast<InitListExpr>(Args[0]); 6443 unsigned NumInits = InitList->getNumInits(); 6444 QualType DestType = Entity.getType(); 6445 QualType E; 6446 bool Success = S.isStdInitializerList(DestType.getNonReferenceType(), &E); 6447 (void)Success; 6448 assert(Success && "Where did the std::initializer_list go?"); 6449 InitializedEntity HiddenArray = InitializedEntity::InitializeTemporary( 6450 S.Context.getConstantArrayType(E, 6451 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()), 6452 NumInits), 6453 ArrayType::Normal, 0)); 6454 InitializedEntity Element = InitializedEntity::InitializeElement(S.Context, 6455 0, HiddenArray); 6456 // Show at most 3 errors. Otherwise, you'd get a lot of errors for errors 6457 // where the init list type is wrong, e.g. 6458 // std::initializer_list<void*> list = { 1, 2, 3, 4, 5, 6, 7, 8 }; 6459 // FIXME: Emit a note if we hit the limit? 6460 int ErrorCount = 0; 6461 for (unsigned i = 0; i < NumInits && ErrorCount < 3; ++i) { 6462 Element.setElementIndex(i); 6463 ExprResult Init = S.Owned(InitList->getInit(i)); 6464 if (S.PerformCopyInitialization(Element, Init.get()->getExprLoc(), Init) 6465 .isInvalid()) 6466 ++ErrorCount; 6467 } 6468 break; 6469 } 6470 6471 case FK_ExplicitConstructor: { 6472 S.Diag(Kind.getLocation(), diag::err_selected_explicit_constructor) 6473 << Args[0]->getSourceRange(); 6474 OverloadCandidateSet::iterator Best; 6475 OverloadingResult Ovl 6476 = FailedCandidateSet.BestViableFunction(S, Kind.getLocation(), Best); 6477 (void)Ovl; 6478 assert(Ovl == OR_Success && "Inconsistent overload resolution"); 6479 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function); 6480 S.Diag(CtorDecl->getLocation(), diag::note_constructor_declared_here); 6481 break; 6482 } 6483 } 6484 6485 PrintInitLocationNote(S, Entity); 6486 return true; 6487} 6488 6489void InitializationSequence::dump(raw_ostream &OS) const { 6490 switch (SequenceKind) { 6491 case FailedSequence: { 6492 OS << "Failed sequence: "; 6493 switch (Failure) { 6494 case FK_TooManyInitsForReference: 6495 OS << "too many initializers for reference"; 6496 break; 6497 6498 case FK_ArrayNeedsInitList: 6499 OS << "array requires initializer list"; 6500 break; 6501 6502 case FK_ArrayNeedsInitListOrStringLiteral: 6503 OS << "array requires initializer list or string literal"; 6504 break; 6505 6506 case FK_ArrayNeedsInitListOrWideStringLiteral: 6507 OS << "array requires initializer list or wide string literal"; 6508 break; 6509 6510 case FK_NarrowStringIntoWideCharArray: 6511 OS << "narrow string into wide char array"; 6512 break; 6513 6514 case FK_WideStringIntoCharArray: 6515 OS << "wide string into char array"; 6516 break; 6517 6518 case FK_IncompatWideStringIntoWideChar: 6519 OS << "incompatible wide string into wide char array"; 6520 break; 6521 6522 case FK_ArrayTypeMismatch: 6523 OS << "array type mismatch"; 6524 break; 6525 6526 case FK_NonConstantArrayInit: 6527 OS << "non-constant array initializer"; 6528 break; 6529 6530 case FK_AddressOfOverloadFailed: 6531 OS << "address of overloaded function failed"; 6532 break; 6533 6534 case FK_ReferenceInitOverloadFailed: 6535 OS << "overload resolution for reference initialization failed"; 6536 break; 6537 6538 case FK_NonConstLValueReferenceBindingToTemporary: 6539 OS << "non-const lvalue reference bound to temporary"; 6540 break; 6541 6542 case FK_NonConstLValueReferenceBindingToUnrelated: 6543 OS << "non-const lvalue reference bound to unrelated type"; 6544 break; 6545 6546 case FK_RValueReferenceBindingToLValue: 6547 OS << "rvalue reference bound to an lvalue"; 6548 break; 6549 6550 case FK_ReferenceInitDropsQualifiers: 6551 OS << "reference initialization drops qualifiers"; 6552 break; 6553 6554 case FK_ReferenceInitFailed: 6555 OS << "reference initialization failed"; 6556 break; 6557 6558 case FK_ConversionFailed: 6559 OS << "conversion failed"; 6560 break; 6561 6562 case FK_ConversionFromPropertyFailed: 6563 OS << "conversion from property failed"; 6564 break; 6565 6566 case FK_TooManyInitsForScalar: 6567 OS << "too many initializers for scalar"; 6568 break; 6569 6570 case FK_ReferenceBindingToInitList: 6571 OS << "referencing binding to initializer list"; 6572 break; 6573 6574 case FK_InitListBadDestinationType: 6575 OS << "initializer list for non-aggregate, non-scalar type"; 6576 break; 6577 6578 case FK_UserConversionOverloadFailed: 6579 OS << "overloading failed for user-defined conversion"; 6580 break; 6581 6582 case FK_ConstructorOverloadFailed: 6583 OS << "constructor overloading failed"; 6584 break; 6585 6586 case FK_DefaultInitOfConst: 6587 OS << "default initialization of a const variable"; 6588 break; 6589 6590 case FK_Incomplete: 6591 OS << "initialization of incomplete type"; 6592 break; 6593 6594 case FK_ListInitializationFailed: 6595 OS << "list initialization checker failure"; 6596 break; 6597 6598 case FK_VariableLengthArrayHasInitializer: 6599 OS << "variable length array has an initializer"; 6600 break; 6601 6602 case FK_PlaceholderType: 6603 OS << "initializer expression isn't contextually valid"; 6604 break; 6605 6606 case FK_ListConstructorOverloadFailed: 6607 OS << "list constructor overloading failed"; 6608 break; 6609 6610 case FK_InitListElementCopyFailure: 6611 OS << "copy construction of initializer list element failed"; 6612 break; 6613 6614 case FK_ExplicitConstructor: 6615 OS << "list copy initialization chose explicit constructor"; 6616 break; 6617 } 6618 OS << '\n'; 6619 return; 6620 } 6621 6622 case DependentSequence: 6623 OS << "Dependent sequence\n"; 6624 return; 6625 6626 case NormalSequence: 6627 OS << "Normal sequence: "; 6628 break; 6629 } 6630 6631 for (step_iterator S = step_begin(), SEnd = step_end(); S != SEnd; ++S) { 6632 if (S != step_begin()) { 6633 OS << " -> "; 6634 } 6635 6636 switch (S->Kind) { 6637 case SK_ResolveAddressOfOverloadedFunction: 6638 OS << "resolve address of overloaded function"; 6639 break; 6640 6641 case SK_CastDerivedToBaseRValue: 6642 OS << "derived-to-base case (rvalue" << S->Type.getAsString() << ")"; 6643 break; 6644 6645 case SK_CastDerivedToBaseXValue: 6646 OS << "derived-to-base case (xvalue" << S->Type.getAsString() << ")"; 6647 break; 6648 6649 case SK_CastDerivedToBaseLValue: 6650 OS << "derived-to-base case (lvalue" << S->Type.getAsString() << ")"; 6651 break; 6652 6653 case SK_BindReference: 6654 OS << "bind reference to lvalue"; 6655 break; 6656 6657 case SK_BindReferenceToTemporary: 6658 OS << "bind reference to a temporary"; 6659 break; 6660 6661 case SK_ExtraneousCopyToTemporary: 6662 OS << "extraneous C++03 copy to temporary"; 6663 break; 6664 6665 case SK_UserConversion: 6666 OS << "user-defined conversion via " << *S->Function.Function; 6667 break; 6668 6669 case SK_QualificationConversionRValue: 6670 OS << "qualification conversion (rvalue)"; 6671 break; 6672 6673 case SK_QualificationConversionXValue: 6674 OS << "qualification conversion (xvalue)"; 6675 break; 6676 6677 case SK_QualificationConversionLValue: 6678 OS << "qualification conversion (lvalue)"; 6679 break; 6680 6681 case SK_LValueToRValue: 6682 OS << "load (lvalue to rvalue)"; 6683 break; 6684 6685 case SK_ConversionSequence: 6686 OS << "implicit conversion sequence ("; 6687 S->ICS->DebugPrint(); // FIXME: use OS 6688 OS << ")"; 6689 break; 6690 6691 case SK_ListInitialization: 6692 OS << "list aggregate initialization"; 6693 break; 6694 6695 case SK_ListConstructorCall: 6696 OS << "list initialization via constructor"; 6697 break; 6698 6699 case SK_UnwrapInitList: 6700 OS << "unwrap reference initializer list"; 6701 break; 6702 6703 case SK_RewrapInitList: 6704 OS << "rewrap reference initializer list"; 6705 break; 6706 6707 case SK_ConstructorInitialization: 6708 OS << "constructor initialization"; 6709 break; 6710 6711 case SK_ZeroInitialization: 6712 OS << "zero initialization"; 6713 break; 6714 6715 case SK_CAssignment: 6716 OS << "C assignment"; 6717 break; 6718 6719 case SK_StringInit: 6720 OS << "string initialization"; 6721 break; 6722 6723 case SK_ObjCObjectConversion: 6724 OS << "Objective-C object conversion"; 6725 break; 6726 6727 case SK_ArrayInit: 6728 OS << "array initialization"; 6729 break; 6730 6731 case SK_ParenthesizedArrayInit: 6732 OS << "parenthesized array initialization"; 6733 break; 6734 6735 case SK_PassByIndirectCopyRestore: 6736 OS << "pass by indirect copy and restore"; 6737 break; 6738 6739 case SK_PassByIndirectRestore: 6740 OS << "pass by indirect restore"; 6741 break; 6742 6743 case SK_ProduceObjCObject: 6744 OS << "Objective-C object retension"; 6745 break; 6746 6747 case SK_StdInitializerList: 6748 OS << "std::initializer_list from initializer list"; 6749 break; 6750 6751 case SK_OCLSamplerInit: 6752 OS << "OpenCL sampler_t from integer constant"; 6753 break; 6754 6755 case SK_OCLZeroEvent: 6756 OS << "OpenCL event_t from zero"; 6757 break; 6758 } 6759 6760 OS << " [" << S->Type.getAsString() << ']'; 6761 } 6762 6763 OS << '\n'; 6764} 6765 6766void InitializationSequence::dump() const { 6767 dump(llvm::errs()); 6768} 6769 6770static void DiagnoseNarrowingInInitList(Sema &S, InitializationSequence &Seq, 6771 QualType EntityType, 6772 const Expr *PreInit, 6773 const Expr *PostInit) { 6774 if (Seq.step_begin() == Seq.step_end() || PreInit->isValueDependent()) 6775 return; 6776 6777 // A narrowing conversion can only appear as the final implicit conversion in 6778 // an initialization sequence. 6779 const InitializationSequence::Step &LastStep = Seq.step_end()[-1]; 6780 if (LastStep.Kind != InitializationSequence::SK_ConversionSequence) 6781 return; 6782 6783 const ImplicitConversionSequence &ICS = *LastStep.ICS; 6784 const StandardConversionSequence *SCS = 0; 6785 switch (ICS.getKind()) { 6786 case ImplicitConversionSequence::StandardConversion: 6787 SCS = &ICS.Standard; 6788 break; 6789 case ImplicitConversionSequence::UserDefinedConversion: 6790 SCS = &ICS.UserDefined.After; 6791 break; 6792 case ImplicitConversionSequence::AmbiguousConversion: 6793 case ImplicitConversionSequence::EllipsisConversion: 6794 case ImplicitConversionSequence::BadConversion: 6795 return; 6796 } 6797 6798 // Determine the type prior to the narrowing conversion. If a conversion 6799 // operator was used, this may be different from both the type of the entity 6800 // and of the pre-initialization expression. 6801 QualType PreNarrowingType = PreInit->getType(); 6802 if (Seq.step_begin() + 1 != Seq.step_end()) 6803 PreNarrowingType = Seq.step_end()[-2].Type; 6804 6805 // C++11 [dcl.init.list]p7: Check whether this is a narrowing conversion. 6806 APValue ConstantValue; 6807 QualType ConstantType; 6808 switch (SCS->getNarrowingKind(S.Context, PostInit, ConstantValue, 6809 ConstantType)) { 6810 case NK_Not_Narrowing: 6811 // No narrowing occurred. 6812 return; 6813 6814 case NK_Type_Narrowing: 6815 // This was a floating-to-integer conversion, which is always considered a 6816 // narrowing conversion even if the value is a constant and can be 6817 // represented exactly as an integer. 6818 S.Diag(PostInit->getLocStart(), 6819 S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11? 6820 diag::warn_init_list_type_narrowing 6821 : S.isSFINAEContext()? 6822 diag::err_init_list_type_narrowing_sfinae 6823 : diag::err_init_list_type_narrowing) 6824 << PostInit->getSourceRange() 6825 << PreNarrowingType.getLocalUnqualifiedType() 6826 << EntityType.getLocalUnqualifiedType(); 6827 break; 6828 6829 case NK_Constant_Narrowing: 6830 // A constant value was narrowed. 6831 S.Diag(PostInit->getLocStart(), 6832 S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11? 6833 diag::warn_init_list_constant_narrowing 6834 : S.isSFINAEContext()? 6835 diag::err_init_list_constant_narrowing_sfinae 6836 : diag::err_init_list_constant_narrowing) 6837 << PostInit->getSourceRange() 6838 << ConstantValue.getAsString(S.getASTContext(), ConstantType) 6839 << EntityType.getLocalUnqualifiedType(); 6840 break; 6841 6842 case NK_Variable_Narrowing: 6843 // A variable's value may have been narrowed. 6844 S.Diag(PostInit->getLocStart(), 6845 S.getLangOpts().MicrosoftExt || !S.getLangOpts().CPlusPlus11? 6846 diag::warn_init_list_variable_narrowing 6847 : S.isSFINAEContext()? 6848 diag::err_init_list_variable_narrowing_sfinae 6849 : diag::err_init_list_variable_narrowing) 6850 << PostInit->getSourceRange() 6851 << PreNarrowingType.getLocalUnqualifiedType() 6852 << EntityType.getLocalUnqualifiedType(); 6853 break; 6854 } 6855 6856 SmallString<128> StaticCast; 6857 llvm::raw_svector_ostream OS(StaticCast); 6858 OS << "static_cast<"; 6859 if (const TypedefType *TT = EntityType->getAs<TypedefType>()) { 6860 // It's important to use the typedef's name if there is one so that the 6861 // fixit doesn't break code using types like int64_t. 6862 // 6863 // FIXME: This will break if the typedef requires qualification. But 6864 // getQualifiedNameAsString() includes non-machine-parsable components. 6865 OS << *TT->getDecl(); 6866 } else if (const BuiltinType *BT = EntityType->getAs<BuiltinType>()) 6867 OS << BT->getName(S.getLangOpts()); 6868 else { 6869 // Oops, we didn't find the actual type of the variable. Don't emit a fixit 6870 // with a broken cast. 6871 return; 6872 } 6873 OS << ">("; 6874 S.Diag(PostInit->getLocStart(), diag::note_init_list_narrowing_override) 6875 << PostInit->getSourceRange() 6876 << FixItHint::CreateInsertion(PostInit->getLocStart(), OS.str()) 6877 << FixItHint::CreateInsertion( 6878 S.getPreprocessor().getLocForEndOfToken(PostInit->getLocEnd()), ")"); 6879} 6880 6881//===----------------------------------------------------------------------===// 6882// Initialization helper functions 6883//===----------------------------------------------------------------------===// 6884bool 6885Sema::CanPerformCopyInitialization(const InitializedEntity &Entity, 6886 ExprResult Init) { 6887 if (Init.isInvalid()) 6888 return false; 6889 6890 Expr *InitE = Init.get(); 6891 assert(InitE && "No initialization expression"); 6892 6893 InitializationKind Kind 6894 = InitializationKind::CreateCopy(InitE->getLocStart(), SourceLocation()); 6895 InitializationSequence Seq(*this, Entity, Kind, InitE); 6896 return !Seq.Failed(); 6897} 6898 6899ExprResult 6900Sema::PerformCopyInitialization(const InitializedEntity &Entity, 6901 SourceLocation EqualLoc, 6902 ExprResult Init, 6903 bool TopLevelOfInitList, 6904 bool AllowExplicit) { 6905 if (Init.isInvalid()) 6906 return ExprError(); 6907 6908 Expr *InitE = Init.get(); 6909 assert(InitE && "No initialization expression?"); 6910 6911 if (EqualLoc.isInvalid()) 6912 EqualLoc = InitE->getLocStart(); 6913 6914 InitializationKind Kind = InitializationKind::CreateCopy(InitE->getLocStart(), 6915 EqualLoc, 6916 AllowExplicit); 6917 InitializationSequence Seq(*this, Entity, Kind, InitE); 6918 Init.release(); 6919 6920 ExprResult Result = Seq.Perform(*this, Entity, Kind, InitE); 6921 6922 if (!Result.isInvalid() && TopLevelOfInitList) 6923 DiagnoseNarrowingInInitList(*this, Seq, Entity.getType(), 6924 InitE, Result.get()); 6925 6926 return Result; 6927} 6928